diff --git a/iamf/cli/codec/opus_encoder.cc b/iamf/cli/codec/opus_encoder.cc
index 42f4deb2..def67fbe 100644
--- a/iamf/cli/codec/opus_encoder.cc
+++ b/iamf/cli/codec/opus_encoder.cc
@@ -151,11 +151,20 @@ absl::Status OpusEncoder::InitializeEncoder() {
       opus_error_code, "Failed to initialize Opus encoder."));
 
   // `OPUS_SET_BITRATE` treats this as the bit-rate for the entire substream.
-  // Configure `libopus` so coupled substreams and mono substreams have the same
+  // Configure `libopus` so coupled substreams and mono substreams have equally
   // effective bit-rate per channel.
-  const auto substream_bitrate = static_cast<opus_int32>(
-      encoder_metadata_.target_bitrate_per_channel() * num_channels_);
-  opus_encoder_ctl(encoder_, OPUS_SET_BITRATE(substream_bitrate));
+  if (num_channels_ > 1) {
+    opus_encoder_ctl(
+        encoder_,
+        OPUS_SET_BITRATE(static_cast<opus_int32>(
+            encoder_metadata_.target_bitrate_per_channel() * num_channels_ *
+                encoder_metadata_.coupling_rate_adjustment() +
+            0.5f)));
+  } else {
+    opus_encoder_ctl(encoder_,
+                     OPUS_SET_BITRATE(static_cast<opus_int32>(
+                         encoder_metadata_.target_bitrate_per_channel())));
+  }
 
   return absl::OkStatus();
 }
diff --git a/iamf/cli/proto/codec_config.proto b/iamf/cli/proto/codec_config.proto
index 94036a2b..5eb78b0b 100644
--- a/iamf/cli/proto/codec_config.proto
+++ b/iamf/cli/proto/codec_config.proto
@@ -40,6 +40,7 @@ message OpusEncoderMetadata {
   optional int32 target_bitrate_per_channel = 1;
   optional OpusApplicationFlag application = 2;
   optional bool use_float_api = 3 [default = true];
+  optional float coupling_rate_adjustment = 4 [default = 1.0];
 }
 
 message OpusDecoderConfig {