diff --git a/sdk/objc/Framework/Headers/WebRTC/RTCAudioSessionConfiguration.h b/sdk/objc/Framework/Headers/WebRTC/RTCAudioSessionConfiguration.h
index 6a02751d29..f3f3d80f85 100644
--- a/sdk/objc/Framework/Headers/WebRTC/RTCAudioSessionConfiguration.h
+++ b/sdk/objc/Framework/Headers/WebRTC/RTCAudioSessionConfiguration.h
@@ -15,11 +15,11 @@
 
 NS_ASSUME_NONNULL_BEGIN
 
-extern const int kRTCAudioSessionPreferredNumberOfChannels;
-extern const double kRTCAudioSessionHighPerformanceSampleRate;
-extern const double kRTCAudioSessionLowComplexitySampleRate;
-extern const double kRTCAudioSessionHighPerformanceIOBufferDuration;
-extern const double kRTCAudioSessionLowComplexityIOBufferDuration;
+RTC_EXTERN const int kRTCAudioSessionPreferredNumberOfChannels;
+RTC_EXTERN const double kRTCAudioSessionHighPerformanceSampleRate;
+RTC_EXTERN const double kRTCAudioSessionLowComplexitySampleRate;
+RTC_EXTERN const double kRTCAudioSessionHighPerformanceIOBufferDuration;
+RTC_EXTERN const double kRTCAudioSessionLowComplexityIOBufferDuration;
 
 // Struct to hold configuration values.
 RTC_EXPORT