diff --git a/services/audioflinger/PlaybackTracks.h b/services/audioflinger/PlaybackTracks.h
index 078ae12..4a1948c 100644
--- a/services/audioflinger/PlaybackTracks.h
+++ b/services/audioflinger/PlaybackTracks.h
@@ -470,7 +470,8 @@
     SourceMetadatas mTrackMetadatas;
     /** Protects mTrackMetadatas against concurrent access. */
     audio_utils::mutex& trackMetadataMutex() const { return mTrackMetadataMutex; }
-    mutable audio_utils::mutex mTrackMetadataMutex;
+    mutable audio_utils::mutex mTrackMetadataMutex{
+            audio_utils::MutexOrder::kOutputTrack_TrackMetadataMutex};
 };  // end of OutputTrack
 
 // playback track, used by PatchPanel