diff --git a/media/base/media_channel.h b/media/base/media_channel.h
index c59a5753a6..b7f5987f6e 100644
--- a/media/base/media_channel.h
+++ b/media/base/media_channel.h
@@ -828,6 +828,10 @@ struct RtcpParameters {
 
 struct MediaChannelParameters {
   virtual ~MediaChannelParameters() = default;
+  // This is the value to be sent in the MID RTP header extension (if the header
+  // extension in included in the list of extensions).
+  // It is also used as a key to map the channnel to its transport.
+  std::string mid;
 
   std::vector<Codec> codecs;
   std::vector<webrtc::RtpExtension> extensions;
@@ -862,9 +866,6 @@ struct MediaChannelParameters {
 
 struct SenderParameters : MediaChannelParameters {
   int max_bandwidth_bps = -1;
-  // This is the value to be sent in the MID RTP header extension (if the header
-  // extension in included in the list of extensions).
-  std::string mid;
   bool extmap_allow_mixed = false;
 
  protected:
diff --git a/media/engine/webrtc_voice_engine.cc b/media/engine/webrtc_voice_engine.cc
index 0232ad8d08..e65d0eb734 100644
--- a/media/engine/webrtc_voice_engine.cc
+++ b/media/engine/webrtc_voice_engine.cc
@@ -2071,6 +2071,7 @@ bool WebRtcVoiceReceiveChannel::SetReceiverParameters(
                    << params.ToString();
   // TODO(pthatcher): Refactor this to be more clean now that we have
   // all the information at once.
+  mid_ = params.mid;
 
   if (!SetRecvCodecs(params.codecs)) {
     return false;
diff --git a/pc/channel.cc b/pc/channel.cc
index af130f8316..45c6e74f64 100644
--- a/pc/channel.cc
+++ b/pc/channel.cc
@@ -878,6 +878,7 @@ bool VoiceChannel::SetLocalContent_w(const MediaContentDescription* content,
       content, header_extensions,
       webrtc::RtpTransceiverDirectionHasRecv(content->direction()),
       &recv_params);
+  recv_params.mid = mid();
 
   if (!media_receive_channel()->SetReceiverParameters(recv_params)) {
     error_desc = StringFormat(