diff --git a/modules/audio_coding/test/EncodeDecodeTest.cc b/modules/audio_coding/test/EncodeDecodeTest.cc
index 4d47e4efef..0bf4de5394 100644
--- a/modules/audio_coding/test/EncodeDecodeTest.cc
+++ b/modules/audio_coding/test/EncodeDecodeTest.cc
@@ -54,7 +54,6 @@ Sender::Sender()
 void Sender::Setup(AudioCodingModule *acm, RTPStream *rtpStream,
                    std::string in_file_name, int sample_rate, size_t channels) {
   struct CodecInst sendCodec;
-  int noOfCodecs = acm->NumberOfCodecs();
   int codecNo;
 
   // Open input file
@@ -69,19 +68,7 @@ void Sender::Setup(AudioCodingModule *acm, RTPStream *rtpStream,
   _pcmFile.FastForward(100);
 
   // Set the codec for the current test.
-  if ((testMode == 0) || (testMode == 1)) {
-    // Set the codec id.
-    codecNo = codeId;
-  } else {
-    // Choose codec on command line.
-    printf("List of supported codec.\n");
-    for (int n = 0; n < noOfCodecs; n++) {
-      EXPECT_EQ(0, acm->Codec(n, &sendCodec));
-      printf("%d %s\n", n, sendCodec.plname);
-    }
-    printf("Choose your codec:");
-    ASSERT_GT(scanf("%d", &codecNo), 0);
-  }
+  codecNo = codeId;
 
   EXPECT_EQ(0, acm->Codec(codecNo, &sendCodec));
 
@@ -150,21 +137,8 @@ void Receiver::Setup(AudioCodingModule *acm, RTPStream *rtpStream,
   file_name = file_stream.str();
   _rtpStream = rtpStream;
 
-  if (testMode == 1) {
-    playSampFreq = recvCodec.plfreq;
-    _pcmFile.Open(file_name, recvCodec.plfreq, "wb+");
-  } else if (testMode == 0) {
-    playSampFreq = 32000;
-    _pcmFile.Open(file_name, 32000, "wb+");
-  } else {
-    printf("\nValid output frequencies:\n");
-    printf("8000\n16000\n32000\n-1,");
-    printf("which means output frequency equal to received signal frequency");
-    printf("\n\nChoose output sampling frequency: ");
-    ASSERT_GT(scanf("%d", &playSampFreq), 0);
-    file_name = webrtc::test::OutputPath() + out_file_name + ".pcm";
-    _pcmFile.Open(file_name, playSampFreq, "wb+");
-  }
+  playSampFreq = 32000;
+  _pcmFile.Open(file_name, 32000, "wb+");
 
   _realPayloadSizeBytes = 0;
   _playoutBuffer = new int16_t[WEBRTC_10MS_PCM_AUDIO];
@@ -249,15 +223,10 @@ void Receiver::Run() {
   }
 }
 
-EncodeDecodeTest::EncodeDecodeTest() {
-  _testMode = 2;
-}
-
-EncodeDecodeTest::EncodeDecodeTest(int testMode) {
-  //testMode == 0 for autotest
-  //testMode == 1 for testing all codecs/parameters
-  //testMode > 1 for specific user-input test (as it was used before)
-  _testMode = testMode;
+EncodeDecodeTest::EncodeDecodeTest(int test_mode) {
+  // There used to be different test modes. The only one still supported is the
+  // "autotest" mode.
+  RTC_CHECK_EQ(0, test_mode);
 }
 
 void EncodeDecodeTest::Perform() {
@@ -275,34 +244,27 @@ void EncodeDecodeTest::Perform() {
   struct CodecInst sendCodecTmp;
   numCodecs = acm->NumberOfCodecs();
 
-  if (_testMode != 2) {
-    for (int n = 0; n < numCodecs; n++) {
-      EXPECT_EQ(0, acm->Codec(n, &sendCodecTmp));
-      if (STR_CASE_CMP(sendCodecTmp.plname, "telephone-event") == 0) {
-        numPars[n] = 0;
-      } else if (STR_CASE_CMP(sendCodecTmp.plname, "cn") == 0) {
-        numPars[n] = 0;
-      } else if (STR_CASE_CMP(sendCodecTmp.plname, "red") == 0) {
-        numPars[n] = 0;
-      } else if (sendCodecTmp.channels == 2) {
-        numPars[n] = 0;
-      } else {
-        numPars[n] = 1;
-      }
+  for (int n = 0; n < numCodecs; n++) {
+    EXPECT_EQ(0, acm->Codec(n, &sendCodecTmp));
+    if (STR_CASE_CMP(sendCodecTmp.plname, "telephone-event") == 0) {
+      numPars[n] = 0;
+    } else if (STR_CASE_CMP(sendCodecTmp.plname, "cn") == 0) {
+      numPars[n] = 0;
+    } else if (STR_CASE_CMP(sendCodecTmp.plname, "red") == 0) {
+      numPars[n] = 0;
+    } else if (sendCodecTmp.channels == 2) {
+      numPars[n] = 0;
+    } else {
+      numPars[n] = 1;
     }
-  } else {
-    numCodecs = 1;
-    numPars[0] = 1;
   }
 
-  _receiver.testMode = _testMode;
-
   // Loop over all mono codecs:
   for (int codeId = 0; codeId < numCodecs; codeId++) {
     // Only encode using real mono encoders, not telephone-event and cng.
     for (int loopPars = 1; loopPars <= numPars[codeId]; loopPars++) {
       // Encode all data to file.
-      std::string fileName = EncodeToFile(1, codeId, codePars, _testMode);
+      std::string fileName = EncodeToFile(1, codeId, codePars);
 
       RTPFile rtpFile;
       rtpFile.Open(fileName.c_str(), "rb");
@@ -320,8 +282,7 @@ void EncodeDecodeTest::Perform() {
 
 std::string EncodeDecodeTest::EncodeToFile(int fileType,
                                            int codeId,
-                                           int* codePars,
-                                           int testMode) {
+                                           int* codePars) {
   std::unique_ptr<AudioCodingModule> acm(AudioCodingModule::Create(
       AudioCodingModule::Config(CreateBuiltinAudioDecoderFactory())));
   RTPFile rtpFile;
@@ -331,7 +292,6 @@ std::string EncodeDecodeTest::EncodeToFile(int fileType,
   rtpFile.WriteHeader();
 
   // Store for auto_test and logging.
-  _sender.testMode = testMode;
   _sender.codeId = codeId;
 
   _sender.Setup(acm.get(), &rtpFile, "audio_coding/testfile32kHz", 32000, 1);
diff --git a/modules/audio_coding/test/EncodeDecodeTest.h b/modules/audio_coding/test/EncodeDecodeTest.h
index 3855bc7d38..f1209c5594 100644
--- a/modules/audio_coding/test/EncodeDecodeTest.h
+++ b/modules/audio_coding/test/EncodeDecodeTest.h
@@ -54,8 +54,6 @@ class Sender {
   void Run();
   bool Add10MsData();
 
-  //for auto_test and logging
-  uint8_t testMode;
   uint8_t codeId;
 
  protected:
@@ -80,7 +78,6 @@ class Receiver {
 
   //for auto_test and logging
   uint8_t codeId;
-  uint8_t testMode;
 
  private:
   PCMFile _pcmFile;
@@ -101,18 +98,13 @@ class Receiver {
 
 class EncodeDecodeTest : public ACMTest {
  public:
-  EncodeDecodeTest();
-  explicit EncodeDecodeTest(int testMode);
+  explicit EncodeDecodeTest(int test_mode);
   void Perform() override;
 
   uint16_t _playoutFreq;
-  uint8_t _testMode;
 
  private:
-  std::string EncodeToFile(int fileType,
-                           int codeId,
-                           int* codePars,
-                           int testMode);
+  std::string EncodeToFile(int fileType, int codeId, int* codePars);
 
  protected:
   Sender _sender;
diff --git a/modules/audio_coding/test/PacketLossTest.cc b/modules/audio_coding/test/PacketLossTest.cc
index 45714c4bfd..d5fbfd1207 100644
--- a/modules/audio_coding/test/PacketLossTest.cc
+++ b/modules/audio_coding/test/PacketLossTest.cc
@@ -142,7 +142,6 @@ void PacketLossTest::Perform() {
   rtpFile.Open(fileName.c_str(), "wb+");
   rtpFile.WriteHeader();
 
-  sender_->testMode = 0;
   sender_->codeId = codec_id;
 
   sender_->Setup(acm.get(), &rtpFile, in_file_name_, sample_rate_hz_, channels_,
@@ -157,7 +156,6 @@ void PacketLossTest::Perform() {
   rtpFile.Open(fileName.c_str(), "rb");
   rtpFile.ReadHeader();
 
-  receiver_->testMode = 0;
   receiver_->codeId = codec_id;
 
   receiver_->Setup(acm.get(), &rtpFile, "packetLoss_out", channels_,