I just released a Mac version of my app using Catalyst. It runs fine on my Mac (Big Sur), and others have reported it works fine on their Big Sur macs. I'm getting emails from users saying it won't run on their Catalina mac. In Deployment Info of my XCode project, I have the minimum Mac target as 10.15 - so I'd assume it would alert me if there was a reason it wouldn't run on Catalina. It obviously passed App Review, and is available to download on Catalina macs. So far, 2 people have let me know about issues. The first said it crashes on launch, and they sent me the crash log. It looks like it's failing to find the OpenAL library at a location on the OS. I'd have assumed that this was just part of Catalina and the Catalyst project. I.e. it's not something that my app should be including and isn't. Here's the error: Process:       PolyNomePro [3702] Path:         /Applications/PolyNomePro.app/Contents/MacOS/PolyNomePro Identifier:      com.larryland.polynomepro Version:       21.03.1 (1365) App Item ID:     1151196826 App External ID:   840647992 Code Type:      X86-64 (Native) Parent Process:    ??? [1] Responsible:     PolyNomePro [3702] User ID:       501 Date/Time:      2021-03-17 16:28:27.574 +0300 OS Version:      Mac OS X 10.15.7 (19H524) Report Version:    12 Anonymous UUID:    1037F4A6-CFC6-D223-CF87-0E52AA81752C Time Awake Since Boot: 8000 seconds System Integrity Protection: enabled Crashed Thread:    0 Exception Type:    EXC_CRASH (SIGABRT) Exception Codes:   0x0000000000000000, 0x0000000000000000 Exception Note:    EXC_CORPSE_NOTIFY Termination Reason:  DYLD, [0x1] Library missing Application Specific Information: dyld: launch, loading dependent libraries Dyld Error Message:  Library not loaded: /System/iOSSupport/System/Library/Frameworks/OpenAL.framework/Versions/A/OpenAL  Referenced from: /Applications/PolyNomePro.app/Contents/MacOS/PolyNomePro  Reason: image not found I even asked this user to try installing XCode in case that iOSSupport folder was something to do with having XCode installed. It didn't make a difference. The second person that reported an issue sent me a screenshot of the dialog that appeared when they try to run the app. It says: PolyNome cannot be opened because of a problem Check with the developer to make sure PolyNome works with this version of macOS. You may need to reinstall the application. Be sure to install any available updates for the application and macOS. This report will be sent to Apple automatically. It seems to me that if it was down to something being deprecated, then it would be less likely to work in Big Sur than in Catalina. Can anyone help me get to the bottom of this? Thanks, Joe

I can no longer run my app in the simulator with a version lower than iOS14. I tried iOS12, iOS12.4, iOS13.7 and they all crash with the same error. This only started since upgrading to Big Sur. Nothing has changed in my code base. This is the code that crashes:     // Provide callback audio rendering function on the unit     // Set input callback     AURenderCallbackStruct callbackStruct;     callbackStruct.inputProc = playbackCallback;     callbackStruct.inputProcRefCon = self;     status = AudioUnitSetProperty(_audioUnit, kAudioUnitProperty_SetRenderCallback, kAudioUnitScope_Input, kOutputBus, &callbackStruct, sizeof(callbackStruct) );     NSAssert1(status == noErr, @"Error setting callback: %d", (int)status);     //start audio     AudioOutputUnitStart(_audioUnit); The error "Thread 1: signal SIGABRT" occurs at the last line... AudioOutputUnitStart(_audioUnit); And the errors in the console are: /Library/Audio/Plug-Ins/HAL/JackRouter.plugin/Contents/MacOS/JackRouter: mach-o, but not built for iOS simulator 2020-11-25 15:17:34.229006-0800 PolyNome[20602:879922] Cannot find function pointer New_JackRouterPlugIn for factory <CFUUID 0x600003f11a80> 7CB18864-927D-48B5-904C-CCFBCFBC7ADD in CFBundle/CFPlugIn 0x7fbe247a7390 </Library/Audio/Plug-Ins/HAL/JackRouter.plugin> (bundle, not loaded) 2020-11-25 15:17:34.461372-0800 PolyNome[20602:880389] [AudioHAL_Client] HALB_IOBufferManager.cpp:226:GetIOBuffer:  HALB_IOBufferManager::GetIOBuffer: the stream index is out of range 2020-11-25 15:17:34.461528-0800 PolyNome[20602:880389] [AudioHAL_Client] HALB_IOBufferManager.cpp:226:GetIOBuffer:  HALB_IOBufferManager::GetIOBuffer: the stream index is out of range 2020-11-25 15:17:34.474317-0800 PolyNome[20602:880389] [aqme] 254: AQDefaultDevice (1): output stream 0: null buffer 2020-11-25 15:17:34.475993-0800 PolyNome[20602:880389] [aqme] 1640: EXCEPTION thrown (-50): - 2020-11-25 15:17:43.424327-0800 PolyNome[20602:879922] RPCTimeout.mm:55:_ReportRPCTimeout: Start: Mach message timeout. Apparently deadlocked. Aborting now. CoreSimulator 732.18.0.2 - Device: iPhone 8 Plus (796F538B-78DA-4FE7-9005-317621931E88) - Runtime: iOS 12.4 (16G73) - DeviceType: iPhone 8 Plus As I said, the only thing that's changed since it last worked is that I upgraded to Big Sur. It runs fine in the iOS Simulator, but not in simulators with a lower iOS version. The Audio Output of the Simulator is set to Internal Speakers. Any help is much appreciated.