diff --git a/services/audioflinger/TrackBase.h b/services/audioflinger/TrackBase.h
index 864daa5..98bf96e 100644
--- a/services/audioflinger/TrackBase.h
+++ b/services/audioflinger/TrackBase.h
@@ -166,6 +166,7 @@
     sp<NBAIO_Source>    mTeeSource;
     bool                mTerminated;
     track_type          mType;      // must be one of TYPE_DEFAULT, TYPE_OUTPUT, TYPE_PATCH ...
+    audio_io_handle_t   mThreadIoHandle; // I/O handle of the thread the track is attached to
 };
 
 // PatchProxyBufferProvider interface is implemented by PatchTrack and PatchRecord.