Why AVSampleBufferDisplayLayer hangs on dealloc?

stack like this, how can I get notification from VideoQueueRemoteClient ? Does anyone ever suffer from this?

1. Thread 0 Crashed:

2. 0 libsystem_kernel.dylib 0x00000001d3f03ea4 _mach_msg_trap :8 (in libsystem_kernel.dylib)

3. 1 libsystem_kernel.dylib 0x00000001d3f0337c _mach_msg :72 (in libsystem_kernel.dylib)

4. 2 MediaToolbox 0x00000001d901dfe4 _FigVideoQueueRemoteClient_Destroy :116 (in MediaToolbox)

5. 3 MediaToolbox 0x00000001d9013624 _videoQueueRemote_Invalidate :88 (in MediaToolbox)

6. 4 MediaToolbox 0x00000001d9013784 _videoQueueRemote_Finalize :32 (in MediaToolbox)

7. 5 CoreMedia 0x00000001d7902b70 _FigBaseObjectFinalize :92 (in CoreMedia)

8. 6 CoreFoundation 0x00000001d430a810 __CFRelease :192 (in CoreFoundation)

9. 7 AVFoundation 0x00000001da4db2a0 -[AVSampleBufferDisplayLayer dealloc] :180 (in AVFoundation)

10. 8 TBMediaPlayer 0x00000001187aeb24 -[VideoRenderAVSampleDisplayView dealloc] VideoRenderAVSampleDisplayView.m:55 (in XXMediaPlayer)