diff --git a/modules/audio_coding/BUILD.gn b/modules/audio_coding/BUILD.gn
index 8cb659fb6c..e3a077a038 100644
--- a/modules/audio_coding/BUILD.gn
+++ b/modules/audio_coding/BUILD.gn
@@ -623,14 +623,18 @@ rtc_static_library("isac_fix") {
 rtc_source_set("isac_fix_common") {
   sources = [
     "codecs/isac/fix/source/codec.h",
+    "codecs/isac/fix/source/entropy_coding.h",
     "codecs/isac/fix/source/fft.c",
     "codecs/isac/fix/source/fft.h",
     "codecs/isac/fix/source/filterbank_internal.h",
     "codecs/isac/fix/source/settings.h",
+    "codecs/isac/fix/source/structs.h",
   ]
   public_configs = [ ":isac_fix_config" ]
   deps = [
+    ":isac_common",
     "../..:typedefs",
+    "../../common_audio",
   ]
 }
 
@@ -663,7 +667,6 @@ rtc_source_set("isac_fix_c") {
     "codecs/isac/fix/source/decode_plc.c",
     "codecs/isac/fix/source/encode.c",
     "codecs/isac/fix/source/entropy_coding.c",
-    "codecs/isac/fix/source/entropy_coding.h",
     "codecs/isac/fix/source/filterbank_tables.c",
     "codecs/isac/fix/source/filterbank_tables.h",
     "codecs/isac/fix/source/filterbanks.c",
@@ -688,7 +691,6 @@ rtc_source_set("isac_fix_c") {
     "codecs/isac/fix/source/pitch_lag_tables.h",
     "codecs/isac/fix/source/spectrum_ar_model_tables.c",
     "codecs/isac/fix/source/spectrum_ar_model_tables.h",
-    "codecs/isac/fix/source/structs.h",
     "codecs/isac/fix/source/transform.c",
     "codecs/isac/fix/source/transform_tables.c",
   ]
@@ -2013,6 +2015,7 @@ if (rtc_include_tests) {
     deps = [
       ":isac",
       ":isac_test_util",
+      "../../common_audio",
     ]
 
     include_dirs = [
diff --git a/modules/audio_coding/codecs/isac/fix/source/arith_routines.c b/modules/audio_coding/codecs/isac/fix/source/arith_routines.c
index 5925d68e35..eaeef50f04 100644
--- a/modules/audio_coding/codecs/isac/fix/source/arith_routines.c
+++ b/modules/audio_coding/codecs/isac/fix/source/arith_routines.c
@@ -16,7 +16,7 @@
  *
  */
 
-#include "arith_routins.h"
+#include "modules/audio_coding/codecs/isac/fix/source/arith_routins.h"
 
 
 /****************************************************************************
diff --git a/modules/audio_coding/codecs/isac/fix/source/arith_routines_hist.c b/modules/audio_coding/codecs/isac/fix/source/arith_routines_hist.c
index f1eb5ae8f7..cad3056b37 100644
--- a/modules/audio_coding/codecs/isac/fix/source/arith_routines_hist.c
+++ b/modules/audio_coding/codecs/isac/fix/source/arith_routines_hist.c
@@ -15,7 +15,7 @@
  *
  */
 
-#include "arith_routins.h"
+#include "modules/audio_coding/codecs/isac/fix/source/arith_routins.h"
 
 
 /****************************************************************************
diff --git a/modules/audio_coding/codecs/isac/fix/source/arith_routines_logist.c b/modules/audio_coding/codecs/isac/fix/source/arith_routines_logist.c
index 808aeb7fd9..8e97960461 100644
--- a/modules/audio_coding/codecs/isac/fix/source/arith_routines_logist.c
+++ b/modules/audio_coding/codecs/isac/fix/source/arith_routines_logist.c
@@ -15,7 +15,7 @@
  *
  */
 
-#include "arith_routins.h"
+#include "modules/audio_coding/codecs/isac/fix/source/arith_routins.h"
 
 /* Tables for piecewise linear cdf functions: y = k*x */
 
diff --git a/modules/audio_coding/codecs/isac/fix/source/arith_routins.h b/modules/audio_coding/codecs/isac/fix/source/arith_routins.h
index 830c52fcaf..25eeecf7fa 100644
--- a/modules/audio_coding/codecs/isac/fix/source/arith_routins.h
+++ b/modules/audio_coding/codecs/isac/fix/source/arith_routins.h
@@ -18,8 +18,7 @@
 #ifndef MODULES_AUDIO_CODING_CODECS_ISAC_FIX_SOURCE_ARITH_ROUTINS_H_
 #define MODULES_AUDIO_CODING_CODECS_ISAC_FIX_SOURCE_ARITH_ROUTINS_H_
 
-#include "structs.h"
-
+#include "modules/audio_coding/codecs/isac/fix/source/structs.h"
 
 /****************************************************************************
  * WebRtcIsacfix_EncLogisticMulti2(...)
diff --git a/modules/audio_coding/codecs/isac/fix/source/bandwidth_estimator.c b/modules/audio_coding/codecs/isac/fix/source/bandwidth_estimator.c
index d926f47e3a..354ae3b571 100644
--- a/modules/audio_coding/codecs/isac/fix/source/bandwidth_estimator.c
+++ b/modules/audio_coding/codecs/isac/fix/source/bandwidth_estimator.c
@@ -18,9 +18,9 @@
  *
  */
 
-#include "bandwidth_estimator.h"
+#include "modules/audio_coding/codecs/isac/fix/source/bandwidth_estimator.h"
 
-#include "settings.h"
+#include "modules/audio_coding/codecs/isac/fix/source/settings.h"
 #include "rtc_base/checks.h"
 
 /* array of quantization levels for bottle neck info; Matlab code: */
diff --git a/modules/audio_coding/codecs/isac/fix/source/bandwidth_estimator.h b/modules/audio_coding/codecs/isac/fix/source/bandwidth_estimator.h
index f80a5876fa..67f8d0782e 100644
--- a/modules/audio_coding/codecs/isac/fix/source/bandwidth_estimator.h
+++ b/modules/audio_coding/codecs/isac/fix/source/bandwidth_estimator.h
@@ -19,8 +19,7 @@
 #ifndef MODULES_AUDIO_CODING_CODECS_ISAC_FIX_SOURCE_BANDWIDTH_ESTIMATOR_H_
 #define MODULES_AUDIO_CODING_CODECS_ISAC_FIX_SOURCE_BANDWIDTH_ESTIMATOR_H_
 
-#include "structs.h"
-
+#include "modules/audio_coding/codecs/isac/fix/source/structs.h"
 
 /****************************************************************************
  * WebRtcIsacfix_InitBandwidthEstimator(...)
diff --git a/modules/audio_coding/codecs/isac/fix/source/codec.h b/modules/audio_coding/codecs/isac/fix/source/codec.h
index 88d40551f2..9b87c40869 100644
--- a/modules/audio_coding/codecs/isac/fix/source/codec.h
+++ b/modules/audio_coding/codecs/isac/fix/source/codec.h
@@ -19,7 +19,7 @@
 #ifndef MODULES_AUDIO_CODING_CODECS_ISAC_FIX_SOURCE_CODEC_H_
 #define MODULES_AUDIO_CODING_CODECS_ISAC_FIX_SOURCE_CODEC_H_
 
-#include "structs.h"
+#include "modules/audio_coding/codecs/isac/fix/source/structs.h"
 
 #ifdef __cplusplus
 extern "C" {
diff --git a/modules/audio_coding/codecs/isac/fix/source/decode.c b/modules/audio_coding/codecs/isac/fix/source/decode.c
index cf2d507cb5..144208818a 100644
--- a/modules/audio_coding/codecs/isac/fix/source/decode.c
+++ b/modules/audio_coding/codecs/isac/fix/source/decode.c
@@ -17,12 +17,12 @@
 
 #include <string.h>
 
-#include "bandwidth_estimator.h"
-#include "codec.h"
-#include "entropy_coding.h"
-#include "pitch_estimator.h"
-#include "settings.h"
-#include "structs.h"
+#include "modules/audio_coding/codecs/isac/fix/source/bandwidth_estimator.h"
+#include "modules/audio_coding/codecs/isac/fix/source/codec.h"
+#include "modules/audio_coding/codecs/isac/fix/source/entropy_coding.h"
+#include "modules/audio_coding/codecs/isac/fix/source/pitch_estimator.h"
+#include "modules/audio_coding/codecs/isac/fix/source/settings.h"
+#include "modules/audio_coding/codecs/isac/fix/source/structs.h"
 
 
 
diff --git a/modules/audio_coding/codecs/isac/fix/source/decode_bwe.c b/modules/audio_coding/codecs/isac/fix/source/decode_bwe.c
index 316f59a5e2..99676504cd 100644
--- a/modules/audio_coding/codecs/isac/fix/source/decode_bwe.c
+++ b/modules/audio_coding/codecs/isac/fix/source/decode_bwe.c
@@ -16,10 +16,10 @@
  */
 
 
-#include "bandwidth_estimator.h"
-#include "codec.h"
-#include "entropy_coding.h"
-#include "structs.h"
+#include "modules/audio_coding/codecs/isac/fix/source/bandwidth_estimator.h"
+#include "modules/audio_coding/codecs/isac/fix/source/codec.h"
+#include "modules/audio_coding/codecs/isac/fix/source/entropy_coding.h"
+#include "modules/audio_coding/codecs/isac/fix/source/structs.h"
 
 
 
diff --git a/modules/audio_coding/codecs/isac/fix/source/decode_plc.c b/modules/audio_coding/codecs/isac/fix/source/decode_plc.c
index e907f2b6a6..873cf951ba 100644
--- a/modules/audio_coding/codecs/isac/fix/source/decode_plc.c
+++ b/modules/audio_coding/codecs/isac/fix/source/decode_plc.c
@@ -17,12 +17,12 @@
 
 #include <string.h>
 
-#include "settings.h"
-#include "entropy_coding.h"
-#include "pitch_estimator.h"
-#include "bandwidth_estimator.h"
-#include "structs.h"
-#include "codec.h"
+#include "modules/audio_coding/codecs/isac/fix/source/settings.h"
+#include "modules/audio_coding/codecs/isac/fix/source/entropy_coding.h"
+#include "modules/audio_coding/codecs/isac/fix/source/pitch_estimator.h"
+#include "modules/audio_coding/codecs/isac/fix/source/bandwidth_estimator.h"
+#include "modules/audio_coding/codecs/isac/fix/source/structs.h"
+#include "modules/audio_coding/codecs/isac/fix/source/codec.h"
 
 
 #define NO_OF_PRIMES 8
diff --git a/modules/audio_coding/codecs/isac/fix/source/entropy_coding.c b/modules/audio_coding/codecs/isac/fix/source/entropy_coding.c
index ed816c0ad7..cb154456d4 100644
--- a/modules/audio_coding/codecs/isac/fix/source/entropy_coding.c
+++ b/modules/audio_coding/codecs/isac/fix/source/entropy_coding.c
@@ -18,14 +18,14 @@
 
 #include <stddef.h>
 
-#include "arith_routins.h"
-#include "spectrum_ar_model_tables.h"
-#include "pitch_gain_tables.h"
-#include "pitch_lag_tables.h"
-#include "entropy_coding.h"
-#include "lpc_tables.h"
-#include "settings.h"
-#include "signal_processing_library.h"
+#include "common_audio/signal_processing/include/signal_processing_library.h"
+#include "modules/audio_coding/codecs/isac/fix/source/arith_routins.h"
+#include "modules/audio_coding/codecs/isac/fix/source/entropy_coding.h"
+#include "modules/audio_coding/codecs/isac/fix/source/lpc_tables.h"
+#include "modules/audio_coding/codecs/isac/fix/source/pitch_gain_tables.h"
+#include "modules/audio_coding/codecs/isac/fix/source/pitch_lag_tables.h"
+#include "modules/audio_coding/codecs/isac/fix/source/settings.h"
+#include "modules/audio_coding/codecs/isac/fix/source/spectrum_ar_model_tables.h"
 #include "rtc_base/sanitizer.h"
 
 /*
diff --git a/modules/audio_coding/codecs/isac/fix/source/entropy_coding.h b/modules/audio_coding/codecs/isac/fix/source/entropy_coding.h
index 31f044de0b..ba7bcde0c0 100644
--- a/modules/audio_coding/codecs/isac/fix/source/entropy_coding.h
+++ b/modules/audio_coding/codecs/isac/fix/source/entropy_coding.h
@@ -19,7 +19,7 @@
 #ifndef MODULES_AUDIO_CODING_CODECS_ISAC_FIX_SOURCE_ENTROPY_CODING_H_
 #define MODULES_AUDIO_CODING_CODECS_ISAC_FIX_SOURCE_ENTROPY_CODING_H_
 
-#include "structs.h"
+#include "modules/audio_coding/codecs/isac/fix/source/structs.h"
 
 /* decode complex spectrum (return number of bytes in stream) */
 int WebRtcIsacfix_DecodeSpec(Bitstr_dec  *streamdata,
diff --git a/modules/audio_coding/codecs/isac/fix/source/entropy_coding_neon.c b/modules/audio_coding/codecs/isac/fix/source/entropy_coding_neon.c
index 2eccdfaa61..0200567880 100644
--- a/modules/audio_coding/codecs/isac/fix/source/entropy_coding_neon.c
+++ b/modules/audio_coding/codecs/isac/fix/source/entropy_coding_neon.c
@@ -14,12 +14,11 @@
  * generic platforms.
  */
 
-#include "entropy_coding.h"
-
 #include <arm_neon.h>
 #include <stddef.h>
 
-#include "signal_processing_library.h"
+#include "modules/audio_coding/codecs/isac/fix/source/entropy_coding.h"
+#include "common_audio/signal_processing/include/signal_processing_library.h"
 #include "rtc_base/checks.h"
 
 void WebRtcIsacfix_MatrixProduct1Neon(const int16_t matrix0[],
diff --git a/modules/audio_coding/codecs/isac/fix/source/fft.c b/modules/audio_coding/codecs/isac/fix/source/fft.c
index 21566f1718..a0ed3f83ce 100644
--- a/modules/audio_coding/codecs/isac/fix/source/fft.c
+++ b/modules/audio_coding/codecs/isac/fix/source/fft.c
@@ -16,7 +16,7 @@
  */
 
 
-#include "fft.h"
+#include "modules/audio_coding/codecs/isac/fix/source/fft.h"
 
 static const int16_t kSortTabFft[240] = {
   0, 60, 120, 180, 20, 80, 140, 200, 40, 100, 160, 220,
diff --git a/modules/audio_coding/codecs/isac/fix/source/fft.h b/modules/audio_coding/codecs/isac/fix/source/fft.h
index 83062eafd4..61ec515aef 100644
--- a/modules/audio_coding/codecs/isac/fix/source/fft.h
+++ b/modules/audio_coding/codecs/isac/fix/source/fft.h
@@ -30,9 +30,7 @@
 #ifndef MODULES_AUDIO_CODING_CODECS_ISAC_FIX_SOURCE_FFT_H_
 #define MODULES_AUDIO_CODING_CODECS_ISAC_FIX_SOURCE_FFT_H_
 
-
-#include "structs.h"
-
+#include "modules/audio_coding/codecs/isac/fix/source/structs.h"
 
 int16_t WebRtcIsacfix_FftRadix16Fastest(int16_t RexQx[], int16_t ImxQx[], int16_t iSign);
 
diff --git a/modules/audio_coding/codecs/isac/fix/source/filterbank_tables.c b/modules/audio_coding/codecs/isac/fix/source/filterbank_tables.c
index 732611b643..f2dec79c2d 100644
--- a/modules/audio_coding/codecs/isac/fix/source/filterbank_tables.c
+++ b/modules/audio_coding/codecs/isac/fix/source/filterbank_tables.c
@@ -16,7 +16,7 @@
  *
  */
 
-#include "filterbank_tables.h"
+#include "modules/audio_coding/codecs/isac/fix/source/filterbank_tables.h"
 
 /* HPstcoeff_in_Q14 = {a1, a2, b1 - b0 * a1, b2 - b0 * a2};
  * In float, they are: {-1.94895953203325f, 0.94984516000000f,
diff --git a/modules/audio_coding/codecs/isac/fix/source/filterbanks.c b/modules/audio_coding/codecs/isac/fix/source/filterbanks.c
index b4583e95d1..6aba8b6a54 100644
--- a/modules/audio_coding/codecs/isac/fix/source/filterbanks.c
+++ b/modules/audio_coding/codecs/isac/fix/source/filterbanks.c
@@ -18,11 +18,11 @@
  *
  */
 
-#include "filterbank_internal.h"
+#include "modules/audio_coding/codecs/isac/fix/source/filterbank_internal.h"
 
-#include "codec.h"
-#include "filterbank_tables.h"
-#include "settings.h"
+#include "modules/audio_coding/codecs/isac/fix/source/codec.h"
+#include "modules/audio_coding/codecs/isac/fix/source/filterbank_tables.h"
+#include "modules/audio_coding/codecs/isac/fix/source/settings.h"
 #include "rtc_base/checks.h"
 
 // Declare a function pointer.
diff --git a/modules/audio_coding/codecs/isac/fix/source/initialize.c b/modules/audio_coding/codecs/isac/fix/source/initialize.c
index 4481f98122..1b82958883 100644
--- a/modules/audio_coding/codecs/isac/fix/source/initialize.c
+++ b/modules/audio_coding/codecs/isac/fix/source/initialize.c
@@ -15,9 +15,9 @@
  *
  */
 
-#include "codec.h"
-#include "structs.h"
-#include "pitch_estimator.h"
+#include "modules/audio_coding/codecs/isac/fix/source/codec.h"
+#include "modules/audio_coding/codecs/isac/fix/source/structs.h"
+#include "modules/audio_coding/codecs/isac/fix/source/pitch_estimator.h"
 
 
 void WebRtcIsacfix_InitMaskingEnc(MaskFiltstr_enc *maskdata) {
diff --git a/modules/audio_coding/codecs/isac/fix/source/lattice.c b/modules/audio_coding/codecs/isac/fix/source/lattice.c
index 81369991d5..1089549aa7 100644
--- a/modules/audio_coding/codecs/isac/fix/source/lattice.c
+++ b/modules/audio_coding/codecs/isac/fix/source/lattice.c
@@ -15,8 +15,8 @@
  *
  */
 
-#include "codec.h"
-#include "settings.h"
+#include "modules/audio_coding/codecs/isac/fix/source/codec.h"
+#include "modules/audio_coding/codecs/isac/fix/source/settings.h"
 #include "rtc_base/sanitizer.h"
 
 #define LATTICE_MUL_32_32_RSFT16(a32a, a32b, b32)                  \
diff --git a/modules/audio_coding/codecs/isac/fix/source/lattice_armv7.S b/modules/audio_coding/codecs/isac/fix/source/lattice_armv7.S
index e2d4318541..67ca4a40ff 100644
--- a/modules/audio_coding/codecs/isac/fix/source/lattice_armv7.S
+++ b/modules/audio_coding/codecs/isac/fix/source/lattice_armv7.S
@@ -26,7 +26,7 @@
 @ r6, r7, r8, r10, r11: scratch
 
 #include "system_wrappers/include/asm_defines.h"
-#include "settings.h"
+#include "modules/audio_coding/codecs/isac/fix/source/settings.h"
 
 GLOBAL_FUNCTION WebRtcIsacfix_FilterArLoop
 .align  2
diff --git a/modules/audio_coding/codecs/isac/fix/source/lattice_c.c b/modules/audio_coding/codecs/isac/fix/source/lattice_c.c
index d2356af514..d9849d6a34 100644
--- a/modules/audio_coding/codecs/isac/fix/source/lattice_c.c
+++ b/modules/audio_coding/codecs/isac/fix/source/lattice_c.c
@@ -14,8 +14,8 @@
  *
  */
 
-#include "settings.h"
-#include "signal_processing_library.h"
+#include "common_audio/signal_processing/include/signal_processing_library.h"
+#include "modules/audio_coding/codecs/isac/fix/source/settings.h"
 #include "typedefs.h"  // NOLINT(build/include)
 
 /* Filter ar_g_Q0[] and ar_f_Q0[] through an AR filter with coefficients
diff --git a/modules/audio_coding/codecs/isac/fix/source/lpc_masking_model.c b/modules/audio_coding/codecs/isac/fix/source/lpc_masking_model.c
index 97e4ce03a4..b538085d14 100644
--- a/modules/audio_coding/codecs/isac/fix/source/lpc_masking_model.c
+++ b/modules/audio_coding/codecs/isac/fix/source/lpc_masking_model.c
@@ -18,9 +18,10 @@
 #include "lpc_masking_model.h"
 
 #include <limits.h>  /* For LLONG_MAX and LLONG_MIN. */
-#include "codec.h"
-#include "entropy_coding.h"
-#include "settings.h"
+
+#include "modules/audio_coding/codecs/isac/fix/source/codec.h"
+#include "modules/audio_coding/codecs/isac/fix/source/entropy_coding.h"
+#include "modules/audio_coding/codecs/isac/fix/source/settings.h"
 
 /* The conversion is implemented by the step-down algorithm */
 void WebRtcSpl_AToK_JSK(
diff --git a/modules/audio_coding/codecs/isac/fix/source/lpc_masking_model.h b/modules/audio_coding/codecs/isac/fix/source/lpc_masking_model.h
index 97d291aca2..d6d1e8f0c0 100644
--- a/modules/audio_coding/codecs/isac/fix/source/lpc_masking_model.h
+++ b/modules/audio_coding/codecs/isac/fix/source/lpc_masking_model.h
@@ -22,7 +22,7 @@
 extern "C" {
 #endif
 
-#include "structs.h"
+#include "modules/audio_coding/codecs/isac/fix/source/structs.h"
 
 void WebRtcIsacfix_GetVars(const int16_t *input,
                            const int16_t *pitchGains_Q12,
diff --git a/modules/audio_coding/codecs/isac/fix/source/lpc_tables.c b/modules/audio_coding/codecs/isac/fix/source/lpc_tables.c
index bc0f129711..df723fdd0b 100644
--- a/modules/audio_coding/codecs/isac/fix/source/lpc_tables.c
+++ b/modules/audio_coding/codecs/isac/fix/source/lpc_tables.c
@@ -16,8 +16,8 @@
  */
 
 
-#include "settings.h"
-#include "lpc_tables.h"
+#include "modules/audio_coding/codecs/isac/fix/source/settings.h"
+#include "modules/audio_coding/codecs/isac/fix/source/lpc_tables.h"
 
 /* indices of KLT coefficients used */
 const uint16_t WebRtcIsacfix_kSelIndGain[12] = {
diff --git a/modules/audio_coding/codecs/isac/fix/source/pitch_estimator.h b/modules/audio_coding/codecs/isac/fix/source/pitch_estimator.h
index 0aa727dd41..994cce7ce9 100644
--- a/modules/audio_coding/codecs/isac/fix/source/pitch_estimator.h
+++ b/modules/audio_coding/codecs/isac/fix/source/pitch_estimator.h
@@ -18,7 +18,7 @@
 #ifndef MODULES_AUDIO_CODING_CODECS_ISAC_FIX_SOURCE_PITCH_ESTIMATOR_H_
 #define MODULES_AUDIO_CODING_CODECS_ISAC_FIX_SOURCE_PITCH_ESTIMATOR_H_
 
-#include "structs.h"
+#include "modules/audio_coding/codecs/isac/fix/source/structs.h"
 
 void WebRtcIsacfix_PitchAnalysis(const int16_t *in,               /* PITCH_FRAME_LEN samples */
                                  int16_t *outQ0,                  /* PITCH_FRAME_LEN+QLOOKAHEAD samples */
diff --git a/modules/audio_coding/codecs/isac/fix/source/pitch_filter_armv6.S b/modules/audio_coding/codecs/isac/fix/source/pitch_filter_armv6.S
index 44fcac86f8..d5b55418dc 100644
--- a/modules/audio_coding/codecs/isac/fix/source/pitch_filter_armv6.S
+++ b/modules/audio_coding/codecs/isac/fix/source/pitch_filter_armv6.S
@@ -14,7 +14,7 @@
 @ Output is bit-exact with the reference C code in pitch_filter.c.
 
 #include "system_wrappers/include/asm_defines.h"
-#include "settings.h"
+#include "modules/audio_coding/codecs/isac/fix/source/settings.h"
 
 GLOBAL_FUNCTION WebRtcIsacfix_PitchFilterCore
 .align  2
diff --git a/modules/audio_coding/codecs/isac/fix/source/pitch_gain_tables.c b/modules/audio_coding/codecs/isac/fix/source/pitch_gain_tables.c
index bfd83b7258..bfbab1950d 100644
--- a/modules/audio_coding/codecs/isac/fix/source/pitch_gain_tables.c
+++ b/modules/audio_coding/codecs/isac/fix/source/pitch_gain_tables.c
@@ -15,7 +15,7 @@
  *
  */
 
-#include "pitch_gain_tables.h"
+#include "modules/audio_coding/codecs/isac/fix/source/pitch_gain_tables.h"
 
 
 /********************* Pitch Filter Gain Coefficient Tables ************************/
diff --git a/modules/audio_coding/codecs/isac/fix/source/pitch_lag_tables.c b/modules/audio_coding/codecs/isac/fix/source/pitch_lag_tables.c
index 4566b6eb78..894716e739 100644
--- a/modules/audio_coding/codecs/isac/fix/source/pitch_lag_tables.c
+++ b/modules/audio_coding/codecs/isac/fix/source/pitch_lag_tables.c
@@ -15,8 +15,8 @@
  *
  */
 
-#include "settings.h"
-#include "pitch_lag_tables.h"
+#include "modules/audio_coding/codecs/isac/fix/source/settings.h"
+#include "modules/audio_coding/codecs/isac/fix/source/pitch_lag_tables.h"
 
 
 /********************* Pitch Filter Gain Coefficient Tables ************************/
diff --git a/modules/audio_coding/codecs/isac/fix/source/spectrum_ar_model_tables.c b/modules/audio_coding/codecs/isac/fix/source/spectrum_ar_model_tables.c
index cf2dea7507..4ef9a338cc 100644
--- a/modules/audio_coding/codecs/isac/fix/source/spectrum_ar_model_tables.c
+++ b/modules/audio_coding/codecs/isac/fix/source/spectrum_ar_model_tables.c
@@ -16,8 +16,8 @@
  *
  */
 
-#include "spectrum_ar_model_tables.h"
-#include "settings.h"
+#include "modules/audio_coding/codecs/isac/fix/source/spectrum_ar_model_tables.h"
+#include "modules/audio_coding/codecs/isac/fix/source/settings.h"
 
 /********************* AR Coefficient Tables ************************/
 
diff --git a/modules/audio_coding/codecs/isac/fix/source/spectrum_ar_model_tables.h b/modules/audio_coding/codecs/isac/fix/source/spectrum_ar_model_tables.h
index 9a7e946396..04fddf52fa 100644
--- a/modules/audio_coding/codecs/isac/fix/source/spectrum_ar_model_tables.h
+++ b/modules/audio_coding/codecs/isac/fix/source/spectrum_ar_model_tables.h
@@ -19,7 +19,7 @@
 #ifndef MODULES_AUDIO_CODING_CODECS_ISAC_FIX_SOURCE_SPECTRUM_AR_MODEL_TABLES_H_
 #define MODULES_AUDIO_CODING_CODECS_ISAC_FIX_SOURCE_SPECTRUM_AR_MODEL_TABLES_H_
 
-#include "settings.h"
+#include "modules/audio_coding/codecs/isac/fix/source/settings.h"
 #include "typedefs.h"  // NOLINT(build/include)
 
 /********************* AR Coefficient Tables ************************/
diff --git a/modules/audio_coding/codecs/isac/main/source/arith_routines.c b/modules/audio_coding/codecs/isac/main/source/arith_routines.c
index 5c901bba00..9d5c6930b1 100644
--- a/modules/audio_coding/codecs/isac/main/source/arith_routines.c
+++ b/modules/audio_coding/codecs/isac/main/source/arith_routines.c
@@ -8,8 +8,8 @@
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
-#include "arith_routines.h"
-#include "settings.h"
+#include "modules/audio_coding/codecs/isac/main/source/arith_routines.h"
+#include "modules/audio_coding/codecs/isac/main/source/settings.h"
 
 
 /*
diff --git a/modules/audio_coding/codecs/isac/main/source/arith_routines.h b/modules/audio_coding/codecs/isac/main/source/arith_routines.h
index 73d0c2306e..d001c68b82 100644
--- a/modules/audio_coding/codecs/isac/main/source/arith_routines.h
+++ b/modules/audio_coding/codecs/isac/main/source/arith_routines.h
@@ -18,8 +18,7 @@
 #ifndef MODULES_AUDIO_CODING_CODECS_ISAC_MAIN_SOURCE_ARITH_ROUTINES_H_
 #define MODULES_AUDIO_CODING_CODECS_ISAC_MAIN_SOURCE_ARITH_ROUTINES_H_
 
-#include "structs.h"
-
+#include "modules/audio_coding/codecs/isac/main/source/structs.h"
 
 int WebRtcIsac_EncLogisticMulti2(
     Bitstr *streamdata,              /* in-/output struct containing bitstream */
diff --git a/modules/audio_coding/codecs/isac/main/source/arith_routines_hist.c b/modules/audio_coding/codecs/isac/main/source/arith_routines_hist.c
index b229c679fc..e948979fd7 100644
--- a/modules/audio_coding/codecs/isac/main/source/arith_routines_hist.c
+++ b/modules/audio_coding/codecs/isac/main/source/arith_routines_hist.c
@@ -8,8 +8,8 @@
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
-#include "settings.h"
-#include "arith_routines.h"
+#include "modules/audio_coding/codecs/isac/main/source/settings.h"
+#include "modules/audio_coding/codecs/isac/main/source/arith_routines.h"
 
 
 /*
diff --git a/modules/audio_coding/codecs/isac/main/source/arith_routines_logist.c b/modules/audio_coding/codecs/isac/main/source/arith_routines_logist.c
index a463d4853a..777780f54f 100644
--- a/modules/audio_coding/codecs/isac/main/source/arith_routines_logist.c
+++ b/modules/audio_coding/codecs/isac/main/source/arith_routines_logist.c
@@ -17,7 +17,7 @@
  */
 
 
-#include "arith_routines.h"
+#include "modules/audio_coding/codecs/isac/main/source/arith_routines.h"
 
 
 
diff --git a/modules/audio_coding/codecs/isac/main/source/bandwidth_estimator.c b/modules/audio_coding/codecs/isac/main/source/bandwidth_estimator.c
index 4a16932341..673f10d446 100644
--- a/modules/audio_coding/codecs/isac/main/source/bandwidth_estimator.c
+++ b/modules/audio_coding/codecs/isac/main/source/bandwidth_estimator.c
@@ -16,14 +16,14 @@
  *
  */
 
-#include "bandwidth_estimator.h"
-#include "settings.h"
-#include "isac.h"
-#include "rtc_base/checks.h"
-
 #include <math.h>
 #include <string.h>
 
+#include "modules/audio_coding/codecs/isac/main/source/bandwidth_estimator.h"
+#include "modules/audio_coding/codecs/isac/main/source/settings.h"
+#include "modules/audio_coding/codecs/isac/main/include/isac.h"
+#include "rtc_base/checks.h"
+
 /* array of quantization levels for bottle neck info; Matlab code: */
 /* sprintf('%4.1ff, ', logspace(log10(5000), log10(40000), 12)) */
 static const float kQRateTableWb[12] =
diff --git a/modules/audio_coding/codecs/isac/main/source/bandwidth_estimator.h b/modules/audio_coding/codecs/isac/main/source/bandwidth_estimator.h
index ddebdcd342..e0ecf55b04 100644
--- a/modules/audio_coding/codecs/isac/main/source/bandwidth_estimator.h
+++ b/modules/audio_coding/codecs/isac/main/source/bandwidth_estimator.h
@@ -19,9 +19,8 @@
 #ifndef MODULES_AUDIO_CODING_CODECS_ISAC_MAIN_SOURCE_BANDWIDTH_ESTIMATOR_H_
 #define MODULES_AUDIO_CODING_CODECS_ISAC_MAIN_SOURCE_BANDWIDTH_ESTIMATOR_H_
 
-#include "structs.h"
-#include "settings.h"
-
+#include "modules/audio_coding/codecs/isac/main/source/settings.h"
+#include "modules/audio_coding/codecs/isac/main/source/structs.h"
 
 #define MIN_ISAC_BW     10000
 #define MIN_ISAC_BW_LB  10000
diff --git a/modules/audio_coding/codecs/isac/main/source/codec.h b/modules/audio_coding/codecs/isac/main/source/codec.h
index d938725b92..af7efc024a 100644
--- a/modules/audio_coding/codecs/isac/main/source/codec.h
+++ b/modules/audio_coding/codecs/isac/main/source/codec.h
@@ -19,8 +19,7 @@
 #ifndef MODULES_AUDIO_CODING_CODECS_ISAC_MAIN_SOURCE_CODEC_H_
 #define MODULES_AUDIO_CODING_CODECS_ISAC_MAIN_SOURCE_CODEC_H_
 
-#include "structs.h"
-
+#include "modules/audio_coding/codecs/isac/main/source/structs.h"
 
 void WebRtcIsac_ResetBitstream(Bitstr* bit_stream);
 
diff --git a/modules/audio_coding/codecs/isac/main/source/crc.c b/modules/audio_coding/codecs/isac/main/source/crc.c
index 2419e24033..1bb0827031 100644
--- a/modules/audio_coding/codecs/isac/main/source/crc.c
+++ b/modules/audio_coding/codecs/isac/main/source/crc.c
@@ -8,9 +8,10 @@
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
-#include "crc.h"
 #include <stdlib.h>
-#include "signal_processing_library.h"
+
+#include "modules/audio_coding/codecs/isac/main/source/crc.h"
+#include "common_audio/signal_processing/include/signal_processing_library.h"
 
 #define POLYNOMIAL 0x04c11db7L
 
diff --git a/modules/audio_coding/codecs/isac/main/source/decode.c b/modules/audio_coding/codecs/isac/main/source/decode.c
index e925efba6e..e13bc5587e 100644
--- a/modules/audio_coding/codecs/isac/main/source/decode.c
+++ b/modules/audio_coding/codecs/isac/main/source/decode.c
@@ -18,18 +18,16 @@
  *
  */
 
-
-#include "codec.h"
-#include "entropy_coding.h"
-#include "pitch_estimator.h"
-#include "bandwidth_estimator.h"
-#include "structs.h"
-#include "settings.h"
-
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 
+#include "modules/audio_coding/codecs/isac/main/source/codec.h"
+#include "modules/audio_coding/codecs/isac/main/source/entropy_coding.h"
+#include "modules/audio_coding/codecs/isac/main/source/pitch_estimator.h"
+#include "modules/audio_coding/codecs/isac/main/source/bandwidth_estimator.h"
+#include "modules/audio_coding/codecs/isac/main/source/structs.h"
+#include "modules/audio_coding/codecs/isac/main/source/settings.h"
 
 /*
  * function to decode the bitstream
diff --git a/modules/audio_coding/codecs/isac/main/source/decode_bwe.c b/modules/audio_coding/codecs/isac/main/source/decode_bwe.c
index 019cc89528..89d970fc75 100644
--- a/modules/audio_coding/codecs/isac/main/source/decode_bwe.c
+++ b/modules/audio_coding/codecs/isac/main/source/decode_bwe.c
@@ -8,10 +8,10 @@
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
-#include "structs.h"
-#include "bandwidth_estimator.h"
-#include "entropy_coding.h"
-#include "codec.h"
+#include "modules/audio_coding/codecs/isac/main/source/structs.h"
+#include "modules/audio_coding/codecs/isac/main/source/bandwidth_estimator.h"
+#include "modules/audio_coding/codecs/isac/main/source/entropy_coding.h"
+#include "modules/audio_coding/codecs/isac/main/source/codec.h"
 
 
 int
diff --git a/modules/audio_coding/codecs/isac/main/source/encode.c b/modules/audio_coding/codecs/isac/main/source/encode.c
index 3f1912b6d3..796382009c 100644
--- a/modules/audio_coding/codecs/isac/main/source/encode.c
+++ b/modules/audio_coding/codecs/isac/main/source/encode.c
@@ -21,20 +21,20 @@
 #include <string.h>
 #include <stdio.h>
 
-#include "structs.h"
-#include "codec.h"
-#include "pitch_estimator.h"
-#include "entropy_coding.h"
-#include "arith_routines.h"
-#include "pitch_gain_tables.h"
-#include "pitch_lag_tables.h"
-#include "spectrum_ar_model_tables.h"
-#include "lpc_tables.h"
-#include "lpc_analysis.h"
-#include "bandwidth_estimator.h"
-#include "lpc_shape_swb12_tables.h"
-#include "lpc_shape_swb16_tables.h"
-#include "lpc_gain_swb_tables.h"
+#include "modules/audio_coding/codecs/isac/main/source/structs.h"
+#include "modules/audio_coding/codecs/isac/main/source/codec.h"
+#include "modules/audio_coding/codecs/isac/main/source/pitch_estimator.h"
+#include "modules/audio_coding/codecs/isac/main/source/entropy_coding.h"
+#include "modules/audio_coding/codecs/isac/main/source/arith_routines.h"
+#include "modules/audio_coding/codecs/isac/main/source/pitch_gain_tables.h"
+#include "modules/audio_coding/codecs/isac/main/source/pitch_lag_tables.h"
+#include "modules/audio_coding/codecs/isac/main/source/spectrum_ar_model_tables.h"
+#include "modules/audio_coding/codecs/isac/main/source/lpc_tables.h"
+#include "modules/audio_coding/codecs/isac/main/source/lpc_analysis.h"
+#include "modules/audio_coding/codecs/isac/main/source/bandwidth_estimator.h"
+#include "modules/audio_coding/codecs/isac/main/source/lpc_shape_swb12_tables.h"
+#include "modules/audio_coding/codecs/isac/main/source/lpc_shape_swb16_tables.h"
+#include "modules/audio_coding/codecs/isac/main/source/lpc_gain_swb_tables.h"
 
 
 #define UB_LOOKAHEAD 24
diff --git a/modules/audio_coding/codecs/isac/main/source/encode_lpc_swb.c b/modules/audio_coding/codecs/isac/main/source/encode_lpc_swb.c
index 64cd4a75ec..0ab2dc1296 100644
--- a/modules/audio_coding/codecs/isac/main/source/encode_lpc_swb.c
+++ b/modules/audio_coding/codecs/isac/main/source/encode_lpc_swb.c
@@ -16,16 +16,15 @@
  *
  */
 
-#include "encode_lpc_swb.h"
-
 #include <math.h>
 #include <stdio.h>
 #include <string.h>
 
-#include "lpc_gain_swb_tables.h"
-#include "lpc_shape_swb12_tables.h"
-#include "lpc_shape_swb16_tables.h"
-#include "settings.h"
+#include "modules/audio_coding/codecs/isac/main/source/encode_lpc_swb.h"
+#include "modules/audio_coding/codecs/isac/main/source/lpc_gain_swb_tables.h"
+#include "modules/audio_coding/codecs/isac/main/source/lpc_shape_swb12_tables.h"
+#include "modules/audio_coding/codecs/isac/main/source/lpc_shape_swb16_tables.h"
+#include "modules/audio_coding/codecs/isac/main/source/settings.h"
 #include "typedefs.h"  // NOLINT(build/include)
 
 /******************************************************************************
diff --git a/modules/audio_coding/codecs/isac/main/source/encode_lpc_swb.h b/modules/audio_coding/codecs/isac/main/source/encode_lpc_swb.h
index 6609644b0c..2fa1c715b3 100644
--- a/modules/audio_coding/codecs/isac/main/source/encode_lpc_swb.h
+++ b/modules/audio_coding/codecs/isac/main/source/encode_lpc_swb.h
@@ -19,8 +19,8 @@
 #ifndef MODULES_AUDIO_CODING_CODECS_ISAC_MAIN_SOURCE_ENCODE_LPC_SWB_H_
 #define MODULES_AUDIO_CODING_CODECS_ISAC_MAIN_SOURCE_ENCODE_LPC_SWB_H_
 
-#include "settings.h"
-#include "structs.h"
+#include "modules/audio_coding/codecs/isac/main/source/settings.h"
+#include "modules/audio_coding/codecs/isac/main/source/structs.h"
 #include "typedefs.h"  // NOLINT(build/include)
 
 /******************************************************************************
diff --git a/modules/audio_coding/codecs/isac/main/source/entropy_coding.c b/modules/audio_coding/codecs/isac/main/source/entropy_coding.c
index b494cc287a..28767afc63 100644
--- a/modules/audio_coding/codecs/isac/main/source/entropy_coding.c
+++ b/modules/audio_coding/codecs/isac/main/source/entropy_coding.c
@@ -17,19 +17,19 @@
  */
 
 
-#include "entropy_coding.h"
-#include "settings.h"
-#include "arith_routines.h"
-#include "signal_processing_library.h"
-#include "spectrum_ar_model_tables.h"
-#include "lpc_tables.h"
-#include "pitch_gain_tables.h"
-#include "pitch_lag_tables.h"
-#include "encode_lpc_swb.h"
-#include "lpc_shape_swb12_tables.h"
-#include "lpc_shape_swb16_tables.h"
-#include "lpc_gain_swb_tables.h"
-#include "os_specific_inline.h"
+#include "common_audio/signal_processing/include/signal_processing_library.h"
+#include "modules/audio_coding/codecs/isac/main/source/entropy_coding.h"
+#include "modules/audio_coding/codecs/isac/main/source/settings.h"
+#include "modules/audio_coding/codecs/isac/main/source/arith_routines.h"
+#include "modules/audio_coding/codecs/isac/main/source/spectrum_ar_model_tables.h"
+#include "modules/audio_coding/codecs/isac/main/source/lpc_tables.h"
+#include "modules/audio_coding/codecs/isac/main/source/pitch_gain_tables.h"
+#include "modules/audio_coding/codecs/isac/main/source/pitch_lag_tables.h"
+#include "modules/audio_coding/codecs/isac/main/source/encode_lpc_swb.h"
+#include "modules/audio_coding/codecs/isac/main/source/lpc_shape_swb12_tables.h"
+#include "modules/audio_coding/codecs/isac/main/source/lpc_shape_swb16_tables.h"
+#include "modules/audio_coding/codecs/isac/main/source/lpc_gain_swb_tables.h"
+#include "modules/audio_coding/codecs/isac/main/source/os_specific_inline.h"
 
 #include <math.h>
 #include <string.h>
diff --git a/modules/audio_coding/codecs/isac/main/source/entropy_coding.h b/modules/audio_coding/codecs/isac/main/source/entropy_coding.h
index 2ccd96b620..7224ad07f7 100644
--- a/modules/audio_coding/codecs/isac/main/source/entropy_coding.h
+++ b/modules/audio_coding/codecs/isac/main/source/entropy_coding.h
@@ -19,8 +19,8 @@
 #ifndef MODULES_AUDIO_CODING_CODECS_ISAC_MAIN_SOURCE_ENTROPY_CODING_H_
 #define MODULES_AUDIO_CODING_CODECS_ISAC_MAIN_SOURCE_ENTROPY_CODING_H_
 
-#include "settings.h"
-#include "structs.h"
+#include "modules/audio_coding/codecs/isac/main/source/settings.h"
+#include "modules/audio_coding/codecs/isac/main/source/structs.h"
 
 /******************************************************************************
  * WebRtcIsac_DecodeSpec()
diff --git a/modules/audio_coding/codecs/isac/main/source/fft.c b/modules/audio_coding/codecs/isac/main/source/fft.c
index c854d8c27c..a3cbd5ef64 100644
--- a/modules/audio_coding/codecs/isac/main/source/fft.c
+++ b/modules/audio_coding/codecs/isac/main/source/fft.c
@@ -123,12 +123,11 @@
  * following two constants should agree with the array dimensions.
  *
  *----------------------------------------------------------------------*/
-#include "fft.h"
 
 #include <stdlib.h>
 #include <math.h>
 
-
+#include "modules/audio_coding/codecs/isac/main/source/fft.h"
 
 /* double precision routine */
 static int
diff --git a/modules/audio_coding/codecs/isac/main/source/fft.h b/modules/audio_coding/codecs/isac/main/source/fft.h
index b583b50268..975015370b 100644
--- a/modules/audio_coding/codecs/isac/main/source/fft.h
+++ b/modules/audio_coding/codecs/isac/main/source/fft.h
@@ -30,9 +30,7 @@
 #ifndef MODULES_AUDIO_CODING_CODECS_ISAC_MAIN_SOURCE_FFT_H_
 #define MODULES_AUDIO_CODING_CODECS_ISAC_MAIN_SOURCE_FFT_H_
 
-
-#include "structs.h"
-
+#include "modules/audio_coding/codecs/isac/main/source/structs.h"
 
 /* double precision routine */
 
diff --git a/modules/audio_coding/codecs/isac/main/source/filter_functions.c b/modules/audio_coding/codecs/isac/main/source/filter_functions.c
index d47eb1fa66..7bd5a79d45 100644
--- a/modules/audio_coding/codecs/isac/main/source/filter_functions.c
+++ b/modules/audio_coding/codecs/isac/main/source/filter_functions.c
@@ -13,9 +13,9 @@
 #ifdef WEBRTC_ANDROID
 #include <stdlib.h>
 #endif
-#include "pitch_estimator.h"
-#include "lpc_analysis.h"
-#include "codec.h"
+#include "modules/audio_coding/codecs/isac/main/source/pitch_estimator.h"
+#include "modules/audio_coding/codecs/isac/main/source/lpc_analysis.h"
+#include "modules/audio_coding/codecs/isac/main/source/codec.h"
 
 
 
diff --git a/modules/audio_coding/codecs/isac/main/source/filterbank_tables.c b/modules/audio_coding/codecs/isac/main/source/filterbank_tables.c
index 0f844af9d2..12caee075c 100644
--- a/modules/audio_coding/codecs/isac/main/source/filterbank_tables.c
+++ b/modules/audio_coding/codecs/isac/main/source/filterbank_tables.c
@@ -11,8 +11,8 @@
 /* filterbank_tables.c*/
 /* This file contains variables that are used in filterbanks.c*/
 
-#include "filterbank_tables.h"
-#include "settings.h"
+#include "modules/audio_coding/codecs/isac/main/source/filterbank_tables.h"
+#include "modules/audio_coding/codecs/isac/main/source/settings.h"
 
 /* The composite all-pass filter factors */
 const float WebRtcIsac_kCompositeApFactorsFloat[4] = {
diff --git a/modules/audio_coding/codecs/isac/main/source/filterbank_tables.h b/modules/audio_coding/codecs/isac/main/source/filterbank_tables.h
index 714e227081..2edb0f0eb3 100644
--- a/modules/audio_coding/codecs/isac/main/source/filterbank_tables.h
+++ b/modules/audio_coding/codecs/isac/main/source/filterbank_tables.h
@@ -19,7 +19,7 @@
 #ifndef MODULES_AUDIO_CODING_CODECS_ISAC_MAIN_SOURCE_FILTERBANK_TABLES_H_
 #define MODULES_AUDIO_CODING_CODECS_ISAC_MAIN_SOURCE_FILTERBANK_TABLES_H_
 
-#include "structs.h"
+#include "modules/audio_coding/codecs/isac/main/source/structs.h"
 
 /********************* Coefficient Tables ************************/
 /* The number of composite all-pass filter factors */
diff --git a/modules/audio_coding/codecs/isac/main/source/filterbanks.c b/modules/audio_coding/codecs/isac/main/source/filterbanks.c
index 671fd321ce..6f1e4db633 100644
--- a/modules/audio_coding/codecs/isac/main/source/filterbanks.c
+++ b/modules/audio_coding/codecs/isac/main/source/filterbanks.c
@@ -18,9 +18,9 @@
  *
  */
 
-#include "settings.h"
-#include "filterbank_tables.h"
-#include "codec.h"
+#include "modules/audio_coding/codecs/isac/main/source/settings.h"
+#include "modules/audio_coding/codecs/isac/main/source/filterbank_tables.h"
+#include "modules/audio_coding/codecs/isac/main/source/codec.h"
 
 /* This function performs all-pass filtering--a series of first order all-pass
  * sections are used to filter the input in a cascade manner.
diff --git a/modules/audio_coding/codecs/isac/main/source/intialize.c b/modules/audio_coding/codecs/isac/main/source/intialize.c
index 01e683c573..57025c6bf2 100644
--- a/modules/audio_coding/codecs/isac/main/source/intialize.c
+++ b/modules/audio_coding/codecs/isac/main/source/intialize.c
@@ -10,12 +10,12 @@
 
 /* encode.c  - Encoding function for the iSAC coder */
 
-#include "structs.h"
-#include "codec.h"
-#include "pitch_estimator.h"
-
 #include <math.h>
 
+#include "modules/audio_coding/codecs/isac/main/source/structs.h"
+#include "modules/audio_coding/codecs/isac/main/source/codec.h"
+#include "modules/audio_coding/codecs/isac/main/source/pitch_estimator.h"
+
 void WebRtcIsac_InitMasking(MaskFiltstr *maskdata) {
 
   int k;
diff --git a/modules/audio_coding/codecs/isac/main/source/lattice.c b/modules/audio_coding/codecs/isac/main/source/lattice.c
index eabe708045..d9d2d65665 100644
--- a/modules/audio_coding/codecs/isac/main/source/lattice.c
+++ b/modules/audio_coding/codecs/isac/main/source/lattice.c
@@ -14,8 +14,6 @@
  * contains the normalized lattice filter routines (MA and AR) for iSAC codec
  *
  */
-#include "settings.h"
-#include "codec.h"
 
 #include <math.h>
 #include <memory.h>
@@ -24,6 +22,9 @@
 #include <stdlib.h>
 #endif
 
+#include "modules/audio_coding/codecs/isac/main/source/settings.h"
+#include "modules/audio_coding/codecs/isac/main/source/codec.h"
+
 /* filter the signal using normalized lattice filter */
 /* MA filter */
 void WebRtcIsac_NormLatticeFilterMa(int orderCoef,
diff --git a/modules/audio_coding/codecs/isac/main/source/lpc_analysis.c b/modules/audio_coding/codecs/isac/main/source/lpc_analysis.c
index 60fc25b98b..dbf33fc116 100644
--- a/modules/audio_coding/codecs/isac/main/source/lpc_analysis.c
+++ b/modules/audio_coding/codecs/isac/main/source/lpc_analysis.c
@@ -8,14 +8,14 @@
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
-#include "lpc_analysis.h"
-#include "settings.h"
-#include "codec.h"
-#include "entropy_coding.h"
-
 #include <math.h>
 #include <string.h>
 
+#include "modules/audio_coding/codecs/isac/main/source/lpc_analysis.h"
+#include "modules/audio_coding/codecs/isac/main/source/settings.h"
+#include "modules/audio_coding/codecs/isac/main/source/codec.h"
+#include "modules/audio_coding/codecs/isac/main/source/entropy_coding.h"
+
 #define LEVINSON_EPS    1.0e-10
 
 
diff --git a/modules/audio_coding/codecs/isac/main/source/lpc_analysis.h b/modules/audio_coding/codecs/isac/main/source/lpc_analysis.h
index 1566ab0d40..c0848ab93e 100644
--- a/modules/audio_coding/codecs/isac/main/source/lpc_analysis.h
+++ b/modules/audio_coding/codecs/isac/main/source/lpc_analysis.h
@@ -18,8 +18,8 @@
 #ifndef MODULES_AUDIO_CODING_CODECS_ISAC_MAIN_SOURCE_LPC_ANALYSIS_H_
 #define MODULES_AUDIO_CODING_CODECS_ISAC_MAIN_SOURCE_LPC_ANALYSIS_H_
 
-#include "settings.h"
-#include "structs.h"
+#include "modules/audio_coding/codecs/isac/main/source/settings.h"
+#include "modules/audio_coding/codecs/isac/main/source/structs.h"
 
 double WebRtcIsac_LevDurb(double *a, double *k, double *r, size_t order);
 
diff --git a/modules/audio_coding/codecs/isac/main/source/lpc_gain_swb_tables.c b/modules/audio_coding/codecs/isac/main/source/lpc_gain_swb_tables.c
index d9073d5e9d..d6e65f3ded 100644
--- a/modules/audio_coding/codecs/isac/main/source/lpc_gain_swb_tables.c
+++ b/modules/audio_coding/codecs/isac/main/source/lpc_gain_swb_tables.c
@@ -16,8 +16,8 @@
  *
  */
 
-#include "lpc_gain_swb_tables.h"
-#include "settings.h"
+#include "modules/audio_coding/codecs/isac/main/source/lpc_gain_swb_tables.h"
+#include "modules/audio_coding/codecs/isac/main/source/settings.h"
 #include "typedefs.h"  // NOLINT(build/include)
 
 const double WebRtcIsac_kQSizeLpcGain = 0.100000;
diff --git a/modules/audio_coding/codecs/isac/main/source/lpc_gain_swb_tables.h b/modules/audio_coding/codecs/isac/main/source/lpc_gain_swb_tables.h
index 5ea537575d..7a5abfd26e 100644
--- a/modules/audio_coding/codecs/isac/main/source/lpc_gain_swb_tables.h
+++ b/modules/audio_coding/codecs/isac/main/source/lpc_gain_swb_tables.h
@@ -19,7 +19,7 @@
 #ifndef MODULES_AUDIO_CODING_CODECS_ISAC_MAIN_SOURCE_LPC_GAIN_SWB_TABLES_H_
 #define MODULES_AUDIO_CODING_CODECS_ISAC_MAIN_SOURCE_LPC_GAIN_SWB_TABLES_H_
 
-#include "settings.h"
+#include "modules/audio_coding/codecs/isac/main/source/settings.h"
 #include "typedefs.h"  // NOLINT(build/include)
 
 extern const double WebRtcIsac_kQSizeLpcGain;
diff --git a/modules/audio_coding/codecs/isac/main/source/lpc_shape_swb12_tables.c b/modules/audio_coding/codecs/isac/main/source/lpc_shape_swb12_tables.c
index 6e64e41479..490866c841 100644
--- a/modules/audio_coding/codecs/isac/main/source/lpc_shape_swb12_tables.c
+++ b/modules/audio_coding/codecs/isac/main/source/lpc_shape_swb12_tables.c
@@ -16,8 +16,8 @@
  *
  */
 
-#include "lpc_shape_swb12_tables.h"
-#include "settings.h"
+#include "modules/audio_coding/codecs/isac/main/source/lpc_shape_swb12_tables.h"
+#include "modules/audio_coding/codecs/isac/main/source/settings.h"
 #include "typedefs.h"  // NOLINT(build/include)
 
 /*
diff --git a/modules/audio_coding/codecs/isac/main/source/lpc_shape_swb12_tables.h b/modules/audio_coding/codecs/isac/main/source/lpc_shape_swb12_tables.h
index c703a6cb4b..7bae0960a7 100644
--- a/modules/audio_coding/codecs/isac/main/source/lpc_shape_swb12_tables.h
+++ b/modules/audio_coding/codecs/isac/main/source/lpc_shape_swb12_tables.h
@@ -19,7 +19,7 @@
 #ifndef MODULES_AUDIO_CODING_CODECS_ISAC_MAIN_SOURCE_LPC_SHAPE_SWB12_TABLES_H_
 #define MODULES_AUDIO_CODING_CODECS_ISAC_MAIN_SOURCE_LPC_SHAPE_SWB12_TABLES_H_
 
-#include "settings.h"
+#include "modules/audio_coding/codecs/isac/main/source/settings.h"
 #include "typedefs.h"  // NOLINT(build/include)
 
 extern const double WebRtcIsac_kMeanLarUb12[UB_LPC_ORDER];
diff --git a/modules/audio_coding/codecs/isac/main/source/lpc_shape_swb16_tables.c b/modules/audio_coding/codecs/isac/main/source/lpc_shape_swb16_tables.c
index 852d07fd73..d03c7b7a56 100644
--- a/modules/audio_coding/codecs/isac/main/source/lpc_shape_swb16_tables.c
+++ b/modules/audio_coding/codecs/isac/main/source/lpc_shape_swb16_tables.c
@@ -16,8 +16,8 @@
  *
  */
 
-#include "lpc_shape_swb16_tables.h"
-#include "settings.h"
+#include "modules/audio_coding/codecs/isac/main/source/lpc_shape_swb16_tables.h"
+#include "modules/audio_coding/codecs/isac/main/source/settings.h"
 #include "typedefs.h"  // NOLINT(build/include)
 
 /*
diff --git a/modules/audio_coding/codecs/isac/main/source/lpc_shape_swb16_tables.h b/modules/audio_coding/codecs/isac/main/source/lpc_shape_swb16_tables.h
index 17a77d7c1d..d828b833a9 100644
--- a/modules/audio_coding/codecs/isac/main/source/lpc_shape_swb16_tables.h
+++ b/modules/audio_coding/codecs/isac/main/source/lpc_shape_swb16_tables.h
@@ -19,7 +19,7 @@
 #ifndef MODULES_AUDIO_CODING_CODECS_ISAC_MAIN_SOURCE_LPC_SHAPE_SWB16_TABLES_H_
 #define MODULES_AUDIO_CODING_CODECS_ISAC_MAIN_SOURCE_LPC_SHAPE_SWB16_TABLES_H_
 
-#include "settings.h"
+#include "modules/audio_coding/codecs/isac/main/source/settings.h"
 #include "typedefs.h"  // NOLINT(build/include)
 
 extern const double WebRtcIsac_kMeanLarUb16[UB_LPC_ORDER];
diff --git a/modules/audio_coding/codecs/isac/main/source/lpc_tables.c b/modules/audio_coding/codecs/isac/main/source/lpc_tables.c
index 909809bc67..461b92eb8a 100644
--- a/modules/audio_coding/codecs/isac/main/source/lpc_tables.c
+++ b/modules/audio_coding/codecs/isac/main/source/lpc_tables.c
@@ -10,8 +10,8 @@
 
 /* coding tables for the KLT coefficients */
 
-#include "lpc_tables.h"
-#include "settings.h"
+#include "modules/audio_coding/codecs/isac/main/source/lpc_tables.h"
+#include "modules/audio_coding/codecs/isac/main/source/settings.h"
 
 /* cdf array for model indicator */
 const uint16_t WebRtcIsac_kQKltModelCdf[4] = {
diff --git a/modules/audio_coding/codecs/isac/main/source/lpc_tables.h b/modules/audio_coding/codecs/isac/main/source/lpc_tables.h
index 9412f2e389..2b02557032 100644
--- a/modules/audio_coding/codecs/isac/main/source/lpc_tables.h
+++ b/modules/audio_coding/codecs/isac/main/source/lpc_tables.h
@@ -18,9 +18,9 @@
 #ifndef MODULES_AUDIO_CODING_CODECS_ISAC_MAIN_SOURCE_LPC_TABLES_H_
 #define MODULES_AUDIO_CODING_CODECS_ISAC_MAIN_SOURCE_LPC_TABLES_H_
 
-#include "structs.h"
+#include "modules/audio_coding/codecs/isac/main/source/structs.h"
 
-#include "settings.h"
+#include "modules/audio_coding/codecs/isac/main/source/settings.h"
 
 #define KLT_STEPSIZE         1.00000000
 #define KLT_NUM_AVG_GAIN     0
diff --git a/modules/audio_coding/codecs/isac/main/source/pitch_estimator.c b/modules/audio_coding/codecs/isac/main/source/pitch_estimator.c
index 090b94ca00..4c0a55833c 100644
--- a/modules/audio_coding/codecs/isac/main/source/pitch_estimator.c
+++ b/modules/audio_coding/codecs/isac/main/source/pitch_estimator.c
@@ -8,8 +8,6 @@
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
-#include "pitch_estimator.h"
-
 #include <math.h>
 #include <memory.h>
 #include <string.h>
@@ -17,6 +15,8 @@
 #include <stdlib.h>
 #endif
 
+#include "modules/audio_coding/codecs/isac/main/source/pitch_estimator.h"
+
 static const double kInterpolWin[8] = {-0.00067556028640,  0.02184247643159, -0.12203175715679,  0.60086484101160,
                                        0.60086484101160, -0.12203175715679,  0.02184247643159, -0.00067556028640};
 
diff --git a/modules/audio_coding/codecs/isac/main/source/pitch_estimator.h b/modules/audio_coding/codecs/isac/main/source/pitch_estimator.h
index 96e1e17ee4..47dab0e7f8 100644
--- a/modules/audio_coding/codecs/isac/main/source/pitch_estimator.h
+++ b/modules/audio_coding/codecs/isac/main/source/pitch_estimator.h
@@ -18,9 +18,7 @@
 #ifndef MODULES_AUDIO_CODING_CODECS_ISAC_MAIN_SOURCE_PITCH_ESTIMATOR_H_
 #define MODULES_AUDIO_CODING_CODECS_ISAC_MAIN_SOURCE_PITCH_ESTIMATOR_H_
 
-#include "structs.h"
-
-
+#include "modules/audio_coding/codecs/isac/main/source/structs.h"
 
 void WebRtcIsac_PitchAnalysis(const double *in,               /* PITCH_FRAME_LEN samples */
                               double *out,                    /* PITCH_FRAME_LEN+QLOOKAHEAD samples */
diff --git a/modules/audio_coding/codecs/isac/main/source/pitch_filter.c b/modules/audio_coding/codecs/isac/main/source/pitch_filter.c
index 24ec63acdf..61cd533ab3 100644
--- a/modules/audio_coding/codecs/isac/main/source/pitch_filter.c
+++ b/modules/audio_coding/codecs/isac/main/source/pitch_filter.c
@@ -8,14 +8,12 @@
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
-#include "pitch_estimator.h"
-
 #include <math.h>
 #include <memory.h>
 #include <stdlib.h>
 
-#include "os_specific_inline.h"
-
+#include "modules/audio_coding/codecs/isac/main/source/pitch_estimator.h"
+#include "modules/audio_coding/codecs/isac/main/source/os_specific_inline.h"
 #include "rtc_base/compile_assert_c.h"
 
 /*
diff --git a/modules/audio_coding/codecs/isac/main/source/pitch_gain_tables.c b/modules/audio_coding/codecs/isac/main/source/pitch_gain_tables.c
index 947d3e7636..080432c3a5 100644
--- a/modules/audio_coding/codecs/isac/main/source/pitch_gain_tables.c
+++ b/modules/audio_coding/codecs/isac/main/source/pitch_gain_tables.c
@@ -8,9 +8,8 @@
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
-#include "pitch_gain_tables.h"
-
-#include "settings.h"
+#include "modules/audio_coding/codecs/isac/main/source/pitch_gain_tables.h"
+#include "modules/audio_coding/codecs/isac/main/source/settings.h"
 
 /* header file for coding tables for the pitch filter side-info in the entropy coder */
 /********************* Pitch Filter Gain Coefficient Tables ************************/
diff --git a/modules/audio_coding/codecs/isac/main/source/pitch_lag_tables.c b/modules/audio_coding/codecs/isac/main/source/pitch_lag_tables.c
index f845a22550..57d12021ac 100644
--- a/modules/audio_coding/codecs/isac/main/source/pitch_lag_tables.c
+++ b/modules/audio_coding/codecs/isac/main/source/pitch_lag_tables.c
@@ -8,8 +8,8 @@
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
-#include "pitch_lag_tables.h"
-#include "settings.h"
+#include "modules/audio_coding/codecs/isac/main/source/pitch_lag_tables.h"
+#include "modules/audio_coding/codecs/isac/main/source/settings.h"
 
 /* header file for coding tables for the pitch filter side-info in the entropy coder */
 /********************* Pitch Filter Gain Coefficient Tables ************************/
diff --git a/modules/audio_coding/codecs/isac/main/source/spectrum_ar_model_tables.c b/modules/audio_coding/codecs/isac/main/source/spectrum_ar_model_tables.c
index 0f6d889225..839d5d4586 100644
--- a/modules/audio_coding/codecs/isac/main/source/spectrum_ar_model_tables.c
+++ b/modules/audio_coding/codecs/isac/main/source/spectrum_ar_model_tables.c
@@ -8,8 +8,8 @@
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
-#include "spectrum_ar_model_tables.h"
-#include "settings.h"
+#include "modules/audio_coding/codecs/isac/main/source/spectrum_ar_model_tables.h"
+#include "modules/audio_coding/codecs/isac/main/source/settings.h"
 
 /********************* AR Coefficient Tables ************************/
 /* cdf for quantized reflection coefficient 1 */
diff --git a/modules/audio_coding/codecs/isac/main/source/spectrum_ar_model_tables.h b/modules/audio_coding/codecs/isac/main/source/spectrum_ar_model_tables.h
index 82ab363adb..1e656eb2bd 100644
--- a/modules/audio_coding/codecs/isac/main/source/spectrum_ar_model_tables.h
+++ b/modules/audio_coding/codecs/isac/main/source/spectrum_ar_model_tables.h
@@ -19,7 +19,7 @@
 #ifndef MODULES_AUDIO_CODING_CODECS_ISAC_MAIN_SOURCE_SPECTRUM_AR_MODEL_TABLES_H_
 #define MODULES_AUDIO_CODING_CODECS_ISAC_MAIN_SOURCE_SPECTRUM_AR_MODEL_TABLES_H_
 
-#include "structs.h"
+#include "modules/audio_coding/codecs/isac/main/source/structs.h"
 
 #define NUM_AR_RC_QUANT_BAUNDARY 12
 
diff --git a/modules/audio_coding/codecs/isac/main/source/transform.c b/modules/audio_coding/codecs/isac/main/source/transform.c
index 8992897f45..bfbfecb654 100644
--- a/modules/audio_coding/codecs/isac/main/source/transform.c
+++ b/modules/audio_coding/codecs/isac/main/source/transform.c
@@ -8,12 +8,13 @@
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
-#include "settings.h"
-#include "fft.h"
-#include "codec.h"
-#include "os_specific_inline.h"
 #include <math.h>
 
+#include "modules/audio_coding/codecs/isac/main/source/settings.h"
+#include "modules/audio_coding/codecs/isac/main/source/fft.h"
+#include "modules/audio_coding/codecs/isac/main/source/codec.h"
+#include "modules/audio_coding/codecs/isac/main/source/os_specific_inline.h"
+
 void WebRtcIsac_InitTransform(TransformTables* tables) {
   int k;
   double fact, phase;
diff --git a/modules/audio_coding/codecs/isac/main/test/ReleaseTest-API/ReleaseTest-API.cc b/modules/audio_coding/codecs/isac/main/test/ReleaseTest-API/ReleaseTest-API.cc
index 33d9efcda1..cedcb9d3f4 100644
--- a/modules/audio_coding/codecs/isac/main/test/ReleaseTest-API/ReleaseTest-API.cc
+++ b/modules/audio_coding/codecs/isac/main/test/ReleaseTest-API/ReleaseTest-API.cc
@@ -19,8 +19,8 @@
 #include <iostream>
 
 /* include API */
-#include "isac.h"
-#include "utility.h"
+#include "modules/audio_coding/codecs/isac/main/include/isac.h"
+#include "modules/audio_coding/codecs/isac/main/util/utility.h"
 #include "rtc_base/format_macros.h"
 
 /* Defines */
diff --git a/modules/audio_coding/codecs/isac/main/test/SwitchingSampRate/SwitchingSampRate.cc b/modules/audio_coding/codecs/isac/main/test/SwitchingSampRate/SwitchingSampRate.cc
index 4194478de7..23de079ad0 100644
--- a/modules/audio_coding/codecs/isac/main/test/SwitchingSampRate/SwitchingSampRate.cc
+++ b/modules/audio_coding/codecs/isac/main/test/SwitchingSampRate/SwitchingSampRate.cc
@@ -13,9 +13,10 @@
 //
 
 #include <iostream>
-#include "isac.h"
-#include "utility.h"
-#include "signal_processing_library.h"
+
+#include "common_audio/signal_processing/include/signal_processing_library.h"
+#include "modules/audio_coding/codecs/isac/main/include/isac.h"
+#include "modules/audio_coding/codecs/isac/main/util/utility.h"
 
 #define MAX_FILE_NAME  500
 #define MAX_NUM_CLIENTS 2
diff --git a/modules/audio_coding/codecs/isac/main/test/simpleKenny.c b/modules/audio_coding/codecs/isac/main/test/simpleKenny.c
index 0d2d2cb375..691d0ca710 100644
--- a/modules/audio_coding/codecs/isac/main/test/simpleKenny.c
+++ b/modules/audio_coding/codecs/isac/main/test/simpleKenny.c
@@ -26,8 +26,8 @@
 #include <math.h>
 
 /* include API */
-#include "isac.h"
-#include "utility.h"
+#include "modules/audio_coding/codecs/isac/main/include/isac.h"
+#include "modules/audio_coding/codecs/isac/main/util/utility.h"
 #include "rtc_base/format_macros.h"
 
 /* max number of samples per frame (= 60 ms frame) */
diff --git a/modules/audio_coding/codecs/isac/main/util/utility.c b/modules/audio_coding/codecs/isac/main/util/utility.c
index d9c4332123..56547b11c2 100644
--- a/modules/audio_coding/codecs/isac/main/util/utility.c
+++ b/modules/audio_coding/codecs/isac/main/util/utility.c
@@ -12,7 +12,8 @@
 #include <stdio.h>
 #include <string.h>
 #include <math.h>
-#include "utility.h"
+
+#include "modules/audio_coding/codecs/isac/main/util/utility.h"
 
 /* function for reading audio data from PCM file */
 int