I am seeing a random crash on the AVAudioEngine startAndReturnError method call. I am not able to reproduce this but I am getting a lot of crash reports from the application on the store. My application mix audio from mulitiple files which I pretty much copy the code from the sample project UsingAVAudioEngineforPlaybackMixingandRecording. I tried to add try-catch block to the call and it does not seem to catch the exception. Any ideas or suggestion on how to debug this? It happens across device models (iPhone, iPad, iPod) and iOS (8 and 9)Thread : Fatal Exception: com.apple.coreaudio.avfaudio0 CoreFoundation 0x23d9468b __exceptionPreprocess1 libobjc.A.dylib 0x35292e17 objc_exception_throw2 CoreFoundation 0x23d94561 +[NSException raise:format:]3 libAVFAudio.dylib 0x22652c21 AVAE_RaiseException(NSString*, ...)4 libAVFAudio.dylib 0x22665dd5 AVAudioEngineGraph::PerformCommand(AUGraphNode&, AVAudioEngineGraph::ENodeCommand, void*, unsigned long) const5 libAVFAudio.dylib 0x226669e3 AVAudioEngineGraph::Initialize()6 libAVFAudio.dylib 0x226a3cc3 AVAudioEngineImpl::Initialize()7 libAVFAudio.dylib 0x226a2bdf AVAudioEngineImpl::Start(NSError**)8 libAVFAudio.dylib 0x226a2b53 -[AVAudioEngine startAndReturnError:]9 Acapella 0x000bd98b __33-[MCAudioMixer initWithMetadata:]_block_invoke (MCAudioMixer.m:182)10 Foundation 0x24b48b39 __22-[__NSObserver _doit:]_block_invoke11 Foundation 0x24b4c80d __NSBLOCKOPERATION_IS_CALLING_OUT_TO_A_BLOCK__12 Foundation 0x24aae217 -[NSBlockOperation main]13 Foundation 0x24aa04e1 -[__NSOperationInternal _start:]14 Foundation 0x24b4eac5 __NSOQSchedule_f15 libdispatch.dylib 0x35994d17 _dispatch_client_callout16 libdispatch.dylib 0x359a30b1 _dispatch_main_queue_callback_4CF$VARIANT$mp17 CoreFoundation 0x23d579ad __CFRUNLOOP_IS_SERVICING_THE_MAIN_DISPATCH_QUEUE__18 CoreFoundation 0x23d55ea7 __CFRunLoopRun19 CoreFoundation 0x23ca9249 CFRunLoopRunSpecific20 CoreFoundation 0x23ca9035 CFRunLoopRunInMode21 GraphicsServices 0x2cd5bad1 GSEventRunModal22 UIKit 0x27ebe8a9 UIApplicationMain23 Acapella 0x0015fc63 main (main.m:14)24 libdyld.dylib 0x359de873 start

I am playing back audio on an AVPlayer while recording audio with AVAcaptureSession. How can I synchronize the recording to the audio playback timeline. I am subtracting both inputLatency & outputLatency from AVAudioSession to the timestamp of the capture audio but the timing seems to be still be off. What other latencies do I need to compensate for?

how do I synchronize playback to AVAudioRecorder start record time? Can I assume AVAudioRecorder uses the clock from CMClockGetHostTimeClock? CMTime referenceTime = CMTimeAdd(CMClockGetTime(self.player.masterClock), CMTimeMakeWithSeconds(2, NSECPERSEC)); //start playback and record 2 seconds after.     [self.player setRate:1.0 time:kCMTimeZero atHostTime:referenceTime];   CMTime syncPTS = CMSyncConvertTime(referenceTime, self.player.masterClock, CMClockGetHostTimeClock());   [self.audioRecorder recordAtTime:CMTimeGetSeconds(syncPTS) forDuration:30]; //audioRecorder is an instance of AVAudioRecorder

Hello, I can record with voice isolated when I run the "using_voice_processing" sample project (link below) on either iPhone 12PRO (iOS 15.6) or iPhone 11 (iOS 16.0.2). Running it on iPhone 14PRO and 14PRO Max does not isolate the voice. I have confirmed voice isolation work with FaceTime on the iPhone 14 but it does not filter out background music when running the sample application. https://developer.apple.com/documentation/avfaudio/audio_engine/using_voice_processing

Will there be VNStatefulRequest versions of these classes?