iOS 15+: crash in OpenAL alSourcePlay → OALSource::UpdateBusFormat → libAudioDSP.dylib (_RegisterAUVoiceIsolation_Unsearchable / _DNNVAD_DestroyInstance)

Environment

Engine: cocos2d / CocosDenshion (SimpleAudioEngine / CDSoundEngine, OpenAL)

Devices/OS: iOS 15+

Crash platform: Bugly

Thread: main thread (com.apple.main-thread)

(If relevant, fill in:)

cocos2d / cocos2d-x version:

Xcode / SDK version:

OpenAL usage: SimpleAudioEngine playEffect(...)

What happens

We have an intermittent crash when playing sound effects:

SimpleAudioEngine::playEffect → CDSoundEngine playSound:sourceGroupId:pitch:pan:gain:loop: → alSourcePlay

Crash is not reliably reproducible locally. We tried:

switching Bluetooth devices

triggering alarms / notifications but could not reproduce.

In Bugly, the issue occurs only on iOS 15 devices (no clear concentration on a specific 15.x minor version).

Sometimes the crash shows:

EXC_BAD_ACCESS KERN_INVALID_ADDRESS 0x0000000000000000 Other times the stack shows a terminate from C++ ABI.

Call stack (from Bugly) 0 libc++abi.dylib std::__terminate(void ()()) + 16 1 libc++abi.dylib std::terminate() + 39 2 libAudioDSP.dylib _DNNVAD_DestroyInstance + 1728459 3 libAudioDSP.dylib _RegisterAUVoiceIsolation_Unsearchable + 1027507 4 libAudioDSP.dylib _DNNVAD_DestroyInstance + 1715459 5 libAudioDSP.dylib _DNNVAD_DestroyInstance + 1721223 6 libAudioDSP.dylib _DNNVAD_DestroyInstance + 1696439 7 OpenAL OALSource::UpdateBusFormat() + 219 8 OpenAL OALSource::ChangeChannelSettings() + 455 9 OpenAL OALSource::SetupMixerBus(CAStreamBasicDescription) + 95 10 OpenAL OALSource::Play() + 1587 11 OpenAL _alSourcePlay + 279 12 JellyBlast -[CDSoundEngine playSound:sourceGroupId:pitch:pan:gain:loop:] + 339 13 JellyBlast CocosDenshion::SimpleAudioEngine::playEffect(...) + 175 ...