iOS AVAudioSession Notify Thread crash.

Good day community,

More than half a year we faced the crash with following callstack:

Crashed: AVAudioSession Notify Thread

0. libEmbeddedSystemAUs.dylib
InterruptionListener(void*, unsigned int, unsigned int, void const*)
1. libEmbeddedSystemAUs.dylib
InterruptionListener(void*, unsigned int, unsigned int, void const*)
2. AudioToolbox
AudioSessionPropertyListeners::CallPropertyListeners(unsigned int, unsigned int, void const*) + 596
3. AudioToolbox
HandleAudioSessionCFTypePropertyChangedMessage(unsigned int, unsigned int, void*, unsigned int) + 1144
4. AudioToolbox
ProcessDeferredMessage(unsigned int, __CFData const*, unsigned int, unsigned int) + 2452
5. AudioToolbox
ASCallbackReceiver_AudioSessionPingMessage + 632
6. AudioToolbox
_XAudioSessionPingMessage + 44
7. libAudioToolboxUtility.dylib
mshMIGPerform + 264
8. CoreFoundation
9. CoreFoundation
__CFRunLoopDoSource1 + 444
10. CoreFoundation
__CFRunLoopRun + 1888
11. CoreFoundation
CFRunLoopRunSpecific + 424
12. AVFAudio
GenericRunLoopThread::Entry(void*) + 156
13. AVFAudio
CAPThread::Entry(CAPThread*) + 204
14. libsystem_pthread.dylib
_pthread_start + 156
15. libsystem_pthread.dylib
thread_start + 8

We use Wwise audio framework as audio playback API. We did reported the problem to Audiokinetic's support, but it seems that the problem is not there. Also we used FMOD sound engine earlier, but we had the same issue.

At this time we have around 100 crash events every day, which makes us upset. Looks like it started from iOS 13. My main problem is that I don't communicate with AudioToolbox or AVFAudio API directly but use thirdparty sound engines instead.

I believe I am not the only who faced this problem. Also there is a discussion at

The last message deserves special attention: where Jeffrey Zhuang made a research. This might be helpful for Apple's support team.

Any help is highly appreciated. Best regards, Sergey.