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Hello community! As I read from https://support.apple.com/kb/SP743?locale=en_US iPhone7 has A10 Fusion chip, which has 4 cores, but [NSProcessInfo processInfo].processorCount returns 2. Also here it is stated that "Unlike most implementations of big.LITTLE, such as the Snapdragon 820 or Exynos 8890, only one core type can be active at a time, either the high-performance or low-power cores, but not both. Thus, the A10 Fusion appears to software and benchmarks as a dual core chip. " Another source tells us that: "Meanwhile it should be noted that while A10 technically has four CPU cores – the two Hurricane cores and the two smaller cores – this is not a heterogeneous design, and only two cores are active at once. So for the purposes of high performance benchmarking, this means we're benchmarking the big cores nearly exclusively." Can anybody confirm this or give the link to apple documentation to prove that? Thanks!

Good day community, More than half a year we faced the crash with following callstack: Crashed: AVAudioSession Notify Thread EXC_BAD_ACCESS KERN_INVALID_ADDRESS 0x0000000000000000 0. libEmbeddedSystemAUs.dylib InterruptionListener(void*, unsigned int, unsigned int, void const*) 1. libEmbeddedSystemAUs.dylib InterruptionListener(void*, unsigned int, unsigned int, void const*) arrow_right 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 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE1_PERFORM_FUNCTION__ + 56 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 https://forum.unity.com/threads/ios-12-crash-audiotoolbox.719675/ The last message deserves special attention: https://zhuanlan.zhihu.com/p/370791950 where Jeffrey Zhuang made a research. This might be helpful for Apple's support team. Any help is highly appreciated. Best regards, Sergey.

Good day community! I took part in Apple's MacOS 12 beta testing program and faced a problem with AVPlayer + AVPlayerLayer video playback. System: Macos 12 Beta 5, Xcode 12.5.1 Problem: If application starts in a fullscreen mode, video is not rendering (while audio stream is playing). If I switched to windowed mode (at runtime) video layer becomes visible. This issue does not happen if application starts in windowed mode, there are no problems with video visibility. I can resize, switch fullscreen, switch back - everything works fine. Also there are no problem with video playback on Macos 11. I provide the simplest application's source code, where one can reproduce the problem. git clone https://github.com/s-petrovskiy/apple-test and follow preparation steps in README.md Steps: 1) Run the program; 2) Switch to fullscreen (by pressing F); 3) Launch video playback (by pressing P); 4) Observe the problem: video layer is not visible while audio is played; 5) Switch back to windowed mode (by pressing F); 6) Observe: video becomes visible. Alternative: 1) Run the program; 2) Do not switch to fullscreen and launch the video playback (by pressing P); 3) Observe: video is visible; 4) Toggle to fullscreen (by pressing F) or resize the window manually; 5) Observe: everything works fine. The simplest playback is roughly implemented as following: having a root NSView. create NSView playerView and set it up with wantsLayer:YES; setFrame:[root bounds]; add as subview via [root addSubview:playerView]; create AVPlayer player; create AVPlayerLayer and init with AVPlayer's instance; set up playerLayer with setAutoresizingMask:kCALayerWidthSizable | lCALayerHeightSizable; setVideoGravityAVLayerVideoGravityResizeAspectFill; setFrame:[videoView bounds]; add playerLayer as sublayer to playerView backing layer (which was automatically created by wantsLayer:YES call) via [playerView.layer addSublayer:playerLayer]; attach playable asset to player; launch playback as [player play]; I have no problems with video playback on MacOS 11 Big Sur and earlier. Do I miss something in my code or may it be MacOS 12's issue? I have read MacOS 12 release notes but haven't found any API or behaviour changes which may be related to my question. Any help is highly appreciated. Best regards.