Are the AudioObject APIs (such as AudioObjectGetPropertyData, AudioObjectSetPropertyData, etc.) thread-safe? Meaning, for the same AudioObjectID is it safe to do things like: Get a property in one thread while setting the same property in another thread Set the same property in two different threads Add and remove property listeners in different threads Put differently, is there any internal synchronization or mutex for this kind of usage or is the burden on the caller? I was unable to find any documentation either way which makes me think that the APIs are not thread-safe.

I have created a demo iOS app to create BLE connection with surrounding headphone. I am able to connect to headphone successfully through my demo iOS app. I can also see in iPhone Bluetooth Setting that headphone is connected but when i am playing music from Spotify/YouTube then music is not being played through headphone. It is still using iPhone speakers. First i am scanning sarounding bluetooth Devices through CBCentralManager and then connecting one of the found device. cBCenteralManager.scanForPeripherals(withServices: nil, options: nil) For connecting: cBCenteralManager.connect(peripheral, options: nil) Do i need to make any code changes while connecting via BLE? I am expecting when i am connecting to headphone via my Demo app. Same connection is visible in iPhone Bluetooth setting too then when i play music on spotify/youtube then sound should be played on headphone and not on iPhone speakers.

【手順】 1.アプリを起動する。 2.ImmersiveSpace1がopenされ、3Dオブジェクトのアニメーションが再生される。 3.アニメーションが終了するとImmersiveSpace1をdismissしてImmersiveSpace2をopenする。 【期待値】 ImmersiveSpace1をopenするとBGMが再生され、ImmersiveSpace2がopenしても引き続きBGMが再生されていること。 【結果】 ImmersiveSpace1をopenするとBGMが再生され、ImmersiveSpace2がopenするとBGMの再生が止まる。 【環境】 ・実機（VisionOS2）にて発生。 ・シミュレータでは発生しない。 ・Xcode：Version 15.2 (15C500b) 【ログ】 ImmersiveSpace2をopenした際に実機で出力されている。シミュレータでは出力されない。 AVAudioSession_iOS.mm:2223 Server returned an error from destroySession:. Error Domain=NSCocoaErrorDomain Code=4099 "The connection to service with pid 39 named com.apple.audio.AudioSession was invalidated from this process." UserInfo={NSDebugDescription=The connection to service with pid 39 named com.apple.audio.AudioSession was invalidated from this process.} 【Procedure】 Launch the application. ImmersiveSpace1 is opened and the animation of the 3D object is played. When the animation finishes, ImmersiveSpace1 is dismissed and ImmersiveSpace2 is opened. 【Expected value】 When ImmersiveSpace1 is opened, the background music should play, and when ImmersiveSpace2 is opened, the background music should continue to play. 【Result】 When ImmersiveSpace1 is opened, the BGM is played, and when ImmersiveSpace2 is opened, the BGM stops playing. 【Environment】 This problem occurs on an actual machine (VisionOS2). It does not occur on the simulator. Xcode: Version 15.2 (15C500b) 【Log】 Output on actual device when ImmersiveSpace is opened. It is not output on the simulator. AVAudioSession_iOS.mm:2223 Server returned an error from destroySession:. Error Domain=NSCocoaErrorDomain Code=4099 "The connection to service with pid 39 named com.apple.audio.AudioSession was invalidated from this UserInfo={NSDebugDescription=The connection to service with pid 39 named com.apple.audio.AudioSession was invalidated from this AudioSession was invalidated from this process.}

Is there any feasible way to get a Core Audio device's system effect status (Voice Isolation, Wide Spectrum)? AVCaptureDevice provides convenience properties for system effects for video devices. I need to get this status for Core Audio input devices.

Hi. I saw that in iOS 18 Beta there is a property "transition" on the Music Kit's ApplicationMusicPlayer. However, in my app I am using MPMusicPlayerApplicationController because I want to play Apple Music songs, local songs and podcasts. But I didn't find an analogue property on MPMusicPlayerApplicationController to specify transitions between songs. Am I missing something? Thanks, Dirk

Hello, We are seeing some strange behaviour when using MPRemoteCommandCenter as well as UIKeyCommand in our app on iOS 17. We are finding that when a UIKeyCommand is trigerred via external keyboard to start playing some music (via our own custom CoreAudio driver), the keyboard becomes unresponsive for a few seconds before UIKeyCommands are triggered again. Strangely enough, if we comment out all our MPRemoteCommandCenter code, the UIKeyCommands work without going into the unresponsive state for a few seconds. ie UIKeyCommands: override open var keyCommands: [UIKeyCommand] { let commands = [UIKeyCommand(title: String(localized: "__PLAY_STOP__"), action: #selector(shortcutPlayStop(_:)), input: " "), UIKeyCommand(title: String(localized: "__PAUSE__"), action: #selector(shortcutPause(_:)), input: "."), /** etc **/] commands.forEach { $0.wantsPriorityOverSystemBehavior = true } return commands } and MPRemoteCommands: MPRemoteCommandCenter.shared().playCommand.addTarget { [weak self] _ in self?.doStuff() // etc return .success } Note this issue did not occur prior to iOS17 🤨 Any ideas what could be going on? Thank you!

Hi, I'm working on a web project that uses the MediaSession API to interface with the media notification on iOS. The issue that I'm experiencing occurs after pressing the play button in the media session modal where the session seems to NOT fire the event handler callback and also kill the media session itself. It's a strange behaviour considering that the pause callback works fine. audio_source = new Audio(url); navigator.mediasession.metadata = { ... // Metadata here }; navigator.mediasession.setActionHandler('play', (details) => { audio_source.play(); } ); navigator.mediasession.setActionHandler('pause', (details) => { audio_source.pause(); } );

Hello, I'm having a problem with my Iphone 12: iOS version: 17.5.1 Model name: Iphone 12 When I call someone it's impossible to communicate, it seems that the microphone is deactivated or that it doesn't respond. I was able to extract the ips file from the "data": stacks+audiomxd-.... Here's an extract: {"bug_type":"288","timestamp":"2024-06-16 22:44:25.00 +0200","os_version":"iPhone OS 17.5.1 (21F90)","roots_installed":0,"incident_id":"7B8604DF-3863-4760-806C-591A90A7A7A4"} { "crashReporterKey" : "6928f591dd9e4d26541855e6d4b6a20d408bdfd1", "exception" : "0xbe18d1ee", "frontmostPids" : [ 34 ], "tuning" : { }, "absoluteTime" : 2954071508880, "product" : "iPhone13,2", "kernel" : "Darwin Kernel Version 23.5.0: Wed May 1 20:35:15 PDT 2024; root:xnu-10063.122.3~3\/RELEASE_ARM64_T8101", "date" : "2024-06-16 22:44:25.08 +0200", "reason" : "XPC message timeout in -[AVAudioSessionRemoteXPCClient getProperty:propertyName:MXProperty:reply:], probably deadlocked. Writing a stackshot and terminating.", "codeSigningMonitor" : 1, "incident" : "7B8604DF-3863-4760-806C-591A90A7A7A4", "build" : "iPhone OS 17.5.1 (21F90)", "roots_installed" : 0, "bug_type" : "288", "pid" : 102, "memoryStatus" : {"compressorSize":38088,"compressions":25391066,"decompressions":20835948,"busyBufferCount":3,"memoryPressureDetails":{"pagesWanted":467,"pagesReclaimed":2085},"pageSize":16384,"memoryPressure":false,"memoryPages":{"active":67555,"throttled":0,"fileBacked":60679,"wired":57187,"purgeable":3679,"inactive":65541,"free":1533,"speculative":2364}}, As you can see, one line states : "reason" : "XPC message timeout in -[AVAudioSessionRemoteXPCClient getProperty:propertyName:MXProperty:reply:], probably deadlocked. Writing a stackshot and terminating.", Deadlock occurs when two or more processes are waiting for resources held by the others, creating a situation where none of the processes can progress. In this case, it seems that the process has tried to recover an audio property, but has remained blocked indefinitely. What reinforces my doubts is that at the end of the .ips is a line that seems to give some informations as to where the problem is : "notes" : ["Requested by audiomxd","_dyld_process_info_create(623) for resampling UUIDs failed with 1","_dyld_process_info_create(2535) for resampling UUIDs failed with 1","_dyld_process_info_create(3181) for resampling UUIDs failed with 1","_dyld_process_info_create(3183) for resampling UUIDs failed with 1","_dyld_process_info_create(3503) for resampling UUIDs failed with 1","resampled 409 of 1813 threads with truncated backtraces from 0 pids: ","resampled 625 of 37 images missing from 175 pids: 75,93,98,178,190,210,...,3627"], Here's what my research yielded. Could you please help me? All calls are useless because the microphone no longer works. Regards

Has anyone noticed when you connect your phone to CarPlay the screen shows up but when you play audio its still coming out of the iPhones speaker.

Hi there, whenever I use any third party editing software, the third clip and clips after that have no audio. Here’s how I did it take any third party editing software put 2 clips, cut one in half and delete the other half, cut a half of the 2nd clip Any fixes?

Hello, my app works as Auv3 plugin. I am interested in copying / pasting LogicPro chord track. After I copy chord track in LogicPro and read UIPasteBoard.general in the app, I can see: ["LogicPasteBoardMarker": <OS_dispatch_data: data[0x3024599c0] = { leaf, size = 1, buf = 0x10a758000 }>] How can I access these data? Thank you.

Just installed macOS Sequoia and observed that the mClientID and mProcessID parameters in the AudioServerPlugInClientInfo structure are empty when called AddDeviceClient and RemoveDeviceClient functions of the AudioServerPlugInDriverInterface. This data is essential to identify the connected client, and its absence breaks the basic functionality of the HAL plugins. FB13858951 ticket filed.

I'm developing an app which use "System Audio Recording Only" API to capture system audio. Is there any API to check if app is authorized? So I can instruct user to give my app with this permission. Thanks.

We are using a VoiceProcessingIO audio unit in our VoIP application on Mac. In certain scenarios, the AudioComponentInstanceNew call blocks for up to five seconds (at least two). We are using the following code to initialize the audio unit: OSStatus status; AudioComponentDescription desc; AudioComponent inputComponent; desc.componentType = kAudioUnitType_Output; desc.componentSubType = kAudioUnitSubType_VoiceProcessingIO; desc.componentFlags = 0; desc.componentFlagsMask = 0; desc.componentManufacturer = kAudioUnitManufacturer_Apple; inputComponent = AudioComponentFindNext(NULL, &desc); status = AudioComponentInstanceNew(inputComponent, &unit); We are having the issue with current MacOS versions on a host of different Macs (x86 and x64 alike). It takes two to three seconds until AudioComponentInstanceNew returns. We also see the following errors in the log multiple times: AUVPAggregate.cpp:2560 AggInpStreamsChanged wait failed and those right after (which I don't know if they matter to this issue): KeystrokeSuppressorCore.cpp:44 ERROR: KeystrokeSuppressor initialization was unsuccessful. Invalid or no plist was provided. AU will be bypassed. vpStrategyManager.mm:486 Error code 2003332927 reported at GetPropertyInfo

Tested with library songs on an app targeted to Mac (Designed for iPad). The same app running on iOS queries the same library songs and the duration is expressed correctly in seconds, as expected for the TimeInterval type. Xcode 15.3 MacOS 14.5 FB13821671

Using the hardware volume buttons on the iPhone, you have 16 steps you can adjust your volume to. I want to implement a volume control slider in my app. I am updating the value of the slider using AVAudioSession.sharedInstance().outputVolume. The problem is that this returns values rounded to the nearest 0 or 5. This makes the slider jump around. .formatted() is not causing this problem. You can recreate the problem using code below. @main struct VolumeTestApp: App { init() { try? AVAudioSession.sharedInstance().setActive(true) } var body: some Scene { WindowGroup { ContentView() } } } struct ContentView: View { @State private var volume = Double() @State private var difference = Double() var body: some View { VStack { Text("The volume changed by \(difference.formatted())") Slider(value: $volume, in: 0...1) } .onReceive(AVAudioSession.sharedInstance().publisher(for: \.outputVolume), perform: { value in volume = Double(value) }) .onChange(of: volume) { oldValue, newValue in // Only used to make the problem more obvious if oldValue > newValue { difference = oldValue - newValue } else { difference = newValue - oldValue } } } } Here is a video of the problem in action: https://share.icloud.com/photos/00fmp7Vq1AkRetxcIP5EXeAZA What am I doing wrong or what can I do to avoid this? Thank you

Hi, we have multiple threads in our CoreAudio server plugin carrying out necessary asynchronous work (namely handling USB callbacks and shuffling the required data to the IO). Although these threads have been set up with the appropriate THREAD_TIME_CONSTRAINT_POLICY (which actually improves it) - on M* processors there is an extremely high, non-realtime amount of jitter of >10ms(!) Now either the runloop notification from the USB stack comes that late or the thread driving the runloop hasn't been set up to correctly handling the callbacks in a timely manner. Since AudioUnits threads requiring to comply to the frame deadlines can join the workgroup of the audio device is there a similar opportunity for the CoreAudio server plugin threads? And if so, how should these correctly be set up? Thanks for any hints! Or pointing me to the docs :)

I'm trying to capture audio samples from the selected output device on macOS using ScreenCaptureKit? Thank you

Hi there, I am encountering an issue in my project which utilizes a speech recognizer and occasionally plays audio files. The problem arises when I configure the AVAudioSession and enable voice processing. The system volume changes unexpectedly and becomes uncontrollable. Specifically, the volume is excessively loud on iPhone but quite low on iPad let audioSession = AVAudioSession.sharedInstance() try audioSession.setCategory(.playAndRecord, mode: .default, options: [.defaultToSpeaker, .allowBluetooth, .interruptSpokenAudioAndMixWithOthers]) try audioSession.setActive(true, options: .notifyOthersOnDeactivation) try audioEngine.inputNode.setVoiceProcessingEnabled(true) try audioEngine.outputNode.setVoiceProcessingEnabled(true) I have provided a sample project here: Sample Project. To reproduce the issue, please follow these steps on a real device: Click on "Play recording" to hear the sound at normal volume. Click on "Start recording" to set up the category and speech recognizer. Click on "Stop recording" to stop the recording. Click on "Play recording" again and observe that the sound volume has changed. Thank you for your assistance.

In my app, I only get one interruption notification when a phone call comes in, and nothing after that. The app uses AVAudioEngine. Is this a bug? A very simple repro is to just register for the notification, but not do anything else with audio: struct ContentView: View { var body: some View { VStack { Image(systemName: "globe") .imageScale(.large) .foregroundStyle(.tint) Text("Hello, world!") } .padding() .onReceive(NotificationCenter.default.publisher(for: AVAudioSession.interruptionNotification)) { event in handleAudioInterruption(event: event) } } private func handleAudioInterruption(event: Notification) { print("handleAudioInterruption") guard let info = event.userInfo, let typeValue = info[AVAudioSessionInterruptionTypeKey] as? UInt, let type = AVAudioSession.InterruptionType(rawValue: typeValue) else { print("missing the stuff") return } if type == .began { print("interruption began") } else if type == .ended { print("interruption ended") guard let optionsValue = info[AVAudioSessionInterruptionOptionKey] as? UInt else { return } if AVAudioSession.InterruptionOptions(rawValue: optionsValue).contains(.shouldResume) { print("should resume") } } } } And do this in the app's init: @main struct InterruptionsApp: App { init() { try! AVAudioSession.sharedInstance().setCategory(.playback, options: []) try! AVAudioSession.sharedInstance().setActive(true) } var body: some Scene { WindowGroup { ContentView() } } }