diff --git a/modules/audio_coding/audio_network_adaptor/audio_network_adaptor_config.cc b/modules/audio_coding/audio_network_adaptor/audio_network_adaptor_config.cc
index c312266..e367e10 100644
--- a/modules/audio_coding/audio_network_adaptor/audio_network_adaptor_config.cc
+++ b/modules/audio_coding/audio_network_adaptor/audio_network_adaptor_config.cc
@@ -19,4 +19,7 @@
 AudioEncoderRuntimeConfig::AudioEncoderRuntimeConfig(
     const AudioEncoderRuntimeConfig& other) = default;
 
+AudioEncoderRuntimeConfig& AudioEncoderRuntimeConfig::operator=(
+    const AudioEncoderRuntimeConfig& other) = default;
+
 }  // namespace webrtc
diff --git a/modules/audio_coding/audio_network_adaptor/include/audio_network_adaptor_config.h b/modules/audio_coding/audio_network_adaptor/include/audio_network_adaptor_config.h
index 5fc68e6..148dec2 100644
--- a/modules/audio_coding/audio_network_adaptor/include/audio_network_adaptor_config.h
+++ b/modules/audio_coding/audio_network_adaptor/include/audio_network_adaptor_config.h
@@ -18,6 +18,7 @@
 struct AudioEncoderRuntimeConfig {
   AudioEncoderRuntimeConfig();
   AudioEncoderRuntimeConfig(const AudioEncoderRuntimeConfig& other);
+  AudioEncoderRuntimeConfig& operator=(const AudioEncoderRuntimeConfig& other);
   ~AudioEncoderRuntimeConfig();
   rtc::Optional<int> bitrate_bps;
   rtc::Optional<int> frame_length_ms;