Hi,
I am getting into a trap. Please check stack-trace, howto fix this?
regards, Joël
stack-trace with ExtAudioFileWrite
Audio
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I am using an AVAudioPlayer to play a "tick" sound once per second in a SwiftUI app.
When running the app on an iPhone 16 (18.2.1) the tick sounds increase in volume after a few seconds. This does not happen in the simulator nor on an iPhone SE 2020 (18.1.1).
Topic:
Media Technologies
SubTopic:
Audio
So,
I've been wondering how fast a an offline STT -> ML Prompt -> TTS roundtrip would be.
Interestingly, for many tests, the SpeechTranscriber (STT) takes the bulk of the time, compared to generating a FoundationModel response and creating the Audio using TTS.
E.g.
InteractionStatistics:
- listeningStarted: 21:24:23 4480 2423
- timeTillFirstAboveNoiseFloor: 01.794
- timeTillLastNoiseAboveFloor: 02.383
- timeTillFirstSpeechDetected: 02.399
- timeTillTranscriptFinalized: 04.510
- timeTillFirstMLModelResponse: 04.938
- timeTillMLModelResponse: 05.379
- timeTillTTSStarted: 04.962
- timeTillTTSFinished: 11.016
- speechLength: 06.054
- timeToResponse: 02.578
- transcript: This is a test.
- mlModelResponse: Sure! I'm ready to help with your test. What do you need help with?
Here, between my audio input ending and the Text-2-Speech starting top play (using AVSpeechUtterance) the total response time was 2.5s.
Of that time, it took the SpeechAnalyzer 2.1s to get the transcript finalized, FoundationModel only took 0.4s to respond (and TTS started playing nearly instantly).
I'm already using reportingOptions: [.volatileResults, .fastResults] so it's probably as fast as possible right now?
I'm just surprised the STT takes so much longer compared to the other parts (all being CoreML based, aren't they?)
AVAudioSessionCategoryOptionAllowBluetooth is marked as deprecated in iOS 8 in iOS 26 beta 5 when this option was not deprecated in iOS 18.6. I think this is a mistake and the deprecation is in iOS 26. Am I right?
It seems that the substitute for this option is "AVAudioSessionCategoryOptionAllowBluetoothHFP". The documentation does not make clear if the behaviour is exactly the same or if any difference should be expected... Has anyone used this option in iOS 26? Should I expect any difference with the current behaviour of "AVAudioSessionCategoryOptionAllowBluetooth"?
Thank you.
My current app implements a custom video player, based on a AVSampleBufferRenderSynchronizer synchronising two renderers:
an AVSampleBufferDisplayLayer receiving decoded CVPixelBuffer-based video CMSampleBuffers,
and an AVSampleBufferAudioRenderer receiving decoded lpcm-based audio CMSampleBuffers.
The AVSampleBufferRenderSynchronizer is started when the first image (in presentation order) is decoded and enqueued, using avSynchronizer.setRate(_ rate: Float, time: CMTime), with rate = 1 and time the presentation timestamp of the first decoded image.
Presentation timestamps of video and audio sample buffers are consistent, and on most streams, the audio and video are correctly synchronized.
However on some network streams, on iOS, the audio and video aren't synchronized, with a time difference that seems to increase with time.
On the other hand, with the same player code and network streams on macOS, the synchronization always works fine.
This reminds me of something I've read, about cases where an AVSampleBufferRenderSynchronizer could not synchronize audio and video, causing them to run with independent and potentially drifting clocks, but I cannot find it again.
So, any help / hints on this sync problem will be greatly appreciated! :)
I’m currently developing an iOS metronome app using DispatchSourceTimer as the timer. The interval is set very small, around 50 milliseconds, and I’m using CFAbsoluteTimeGetCurrent to calculate the elapsed time to ensure the beat is played within a ±0.003-second margin.
The problem is that once the app goes to the background, the timing becomes unstable—it slows down noticeably, then recovers after 1–2 seconds.
When coming back to the foreground, it suddenly speeds up, and again, it takes 1–2 seconds to return to normal. It feels like the app is randomly “powering off” and then “overclocking.” It’s super frustrating.
I’ve noticed that some metronome apps in the App Store have similar issues, but there’s one called “Professional Metronome” that’s rock solid with no such problems. What kind of magic are they using? Any experts out there who can help? Thanks in advance!
P.S. I’ve already enabled background audio permissions.
The professional metronome that has no issues: https://link.zhihu.com/?target=https%3A//apps.apple.com/cn/app/pro-metronome-%25E4%25B8%2593%25E4%25B8%259A%25E8%258A%2582%25E6%258B%258D%25E5%2599%25A8/id477960671
Hi all,
with my app ScreenFloat, you can record your screen, along with system- and microphone audio.
Those two audio feeds are recorded into separate audio tracks in order to individually remove or edit them later on.
Now, these recordings you create with ScreenFloat can be drag-and-dropped to other apps instantly. So far, so good, but some apps, like Slack, or VLC, or even websites like YouTube, do not play back multiple audio tracks, just one.
So what I'm trying to do is, on dragging the video recording file out of ScreenFloat, instantly baking together the two individual audio tracks into one, and offering that new file as the drag and drop file, so that all audio is played in the target app.
But it's slow. I mean, it's actually quite fast, but for drag and drop, it's slow.
My approach is this:
"Bake together" the two audio tracks into a one-track m4a audio file using AVMutableAudioMix and AVAssetExportSession
Take the video track, add the new audio file as an audio track to it, and render that out using AVAssetExportSession
For a quick benchmark, a 3'40'' movie, step 1 takes ~1.7 seconds, and step two adds another ~1.5 seconds, so we're at ~3.2 seconds. That's an eternity for a drag and drop, where the user might cancel if there's no immediate feedback.
I could also do it in one step, but then I couldn't use the AV*Passthrough preset, and that makes it take around 32 seconds then, because I assume it touches the video data (which is unnecessary in this case, so I think the two-step approach here is the fastest).
So, my question is, is there a faster way?
The best idea I can come up with right now is, when initially recording the screen with system- and microphone audio as separate tracks, to also record both of them into a third, muted, "hidden" track I could use later on, basically eliminating the need for step one and just ripping the two single audio tracks out of the movie and only have the video and the "hidden" track (then unmuted), but I'd still have a ~1.5 second delay there. Also, there's the processing and data overhead (basically doubling the movie's audio data).
All this would be great for an export operation (where one expects it to take a little time), but for a drag-and-drop operation, it's not ideal.
I've discarded the idea of doing a promise file drag, because many apps do not accept those, and I want to keep wide compatibility with all sorts of apps.
I'd appreciate any ideas or pointers.
Thank you kindly,
Matthias
Hi,
our CourAudio server plugin utilizes the SystemConfiguration.framework to store and restore specific shared system wide settings.
While our application can authenticate to utilize the SystemConfiguration.framework to gain write access to the shared configuration settings the CoreAudio server plugin obviously can't have any user interaction and therefor does not authenticate.
Is it possible to authenticate the CoreAudio server plugin to gain write permissions? Are there any entitlements or other means that would allow this?
Thanks!
Topic:
Media Technologies
SubTopic:
Audio
Tags:
System Configuration
Core Audio
Inter-process communication
Service Management
Hello,
I have an iOS app that is recording audio that is working fine on iPads/iPhones. It asks for microphone permission and after that recording works.
I installed the same app on my M3 MacBook via TestFlight since iPad apps are supposed to work without a change that way. The app starts fine and everything, but it never asks for Microphone permission, so I can't record.
Do I need to do something to make this happen (this is not macCatalyst, its running the arm64 iPhone binary on macOS)
thanks
I have used AVQueuePlayer in my music app to play sequence of audios from a remote server, this how I have defined things my player in my ViewModel
Variables
private var cancellables = Set()
private let audioSession = AVAudioSession.sharedInstance()
private var avQueuePlayer: AVQueuePlayer?
@Published var playbackSpeed: Float = 1.0
before starting playback, I am making sure that audio session is set properly, the code snippet used for that is
do {
try audioSession.setCategory(.playback, mode: .default, options: [])
try audioSession.setActive(true, options: [])
} catch {
return
}
and this is the function I am using to update playback speed
func updatePlaybackSpeed(_ newSpeed: Float){
if newSpeed > 0.0, newSpeed <= 2.0{
playbackSpeed = newSpeed
avQueuePlayer?.rate = newSpeed
print("requested speed is (newSpeed) and actual speed is (String(describing: avQueuePlayer?.rate))")
}
}
sometimes whatever speed is set, player seems to play at the same speed as it was set,
e.g. Once I got "requested speed is 1.5 and actual speed is 1.5", and player also seemed to play at the speed of 1.5
but another time I got "requested speed is 2.0 and actual speed is 2.0", but player still seemed to play at the speed of 1.0
to observe changes in rate, I used this
**private func observeRateChanges() {
guard let avQueuePlayer = self.avQueuePlayer else { return }
NotificationCenter.default.publisher(for: AVQueuePlayer.rateDidChangeNotification, object: avQueuePlayer)
.compactMap { $0.userInfo?[AVPlayer.rateDidChangeReasonKey] as? AVPlayer.RateDidChangeReason }
.sink { reason in
switch reason {
case .appBackgrounded:
print("The app transitioned to the background.")
case .audioSessionInterrupted:
print("The system interrupts the app’s audio session.")
case .setRateCalled:
print("The app set the player’s rate.")
case .setRateFailed:
print("An attempt to change the player’s rate failed.")
default:
break
}
}
.store(in: &cancellables)
}**
when rate was set properly, I got this "The app set the player’s rate." from the above function, but when it wasn't, I got this "An attempt to change the player’s rate failed.,"
now I am not able to understand why rate is not being set, and if it gave "requested speed is 2.0 and actual speed is 2.0" from updatePlaybackSpeed function, why does the player seems to play with the speed of 1.0?
Topic:
Media Technologies
SubTopic:
Audio
I have a memory leak, when using AVAudioPlayer. I managed to narrow down the issue into a very simple app, which code I paste in at the end.
The memory leak start immediately when I start playing sound, but only in the emylator. On the real iPhone there is no memory leak.
The memory leak on the Simulator looks like this:
import SwiftUI
import AVFoundation
struct ContentView_Audio: View {
var sound: AVAudioPlayer?
init() {
guard let path = Bundle.main.path(forResource: "cd201", ofType: "mp3") else { return }
let url = URL(fileURLWithPath: path)
do {
try AVAudioSession.sharedInstance().setCategory(.playback, mode: .default, options: [.mixWithOthers])
} catch {
return
}
do {
try AVAudioSession.sharedInstance().setActive(true)
} catch {
return
}
do {
sound = try AVAudioPlayer(contentsOf: url)
} catch {
return
}
}
var body: some View {
HStack {
Button {
playSound()
} label: {
ZStack {
Circle()
.fill(.mint.opacity(0.3))
.frame(width: 44, height: 44)
.shadow(radius: 8)
Image(systemName: "play.fill")
.resizable()
.frame(width: 20, height: 20)
}
}
.padding()
Button {
stopSound()
} label: {
ZStack {
Circle()
.fill(.mint.opacity(0.3))
.frame(width: 44, height: 44)
.shadow(radius: 8)
Image(systemName: "stop.fill")
.resizable()
.frame(width: 20, height: 20)
}
}
.padding()
}
}
private func playSound() {
guard sound != nil else { return }
sound?.volume = 1
// sound?.numberOfLoops = -1
sound?.play()
}
func stopSound() {
sound?.stop()
}
}
Hello,
I have an existing AUv3 instrument plugin. In the plug in, users can access files (audio files, song projects) via a UIDocumentPickerViewController
In Logic Pro, (and some other hosts, but not all), the document picker is unable to receive touches, while a keyboard case is attached to the iPad.
Removing the case (this is an Apple brand iPad case) allows the interactions to resume and allows me to pick files in the usual way.
One of my users reports this non-responsive behavior occurs even after disconnecting their keyboard.
I have fiddled with entitlements all day, and have determined that is not the issue, since the keyboard disconnection appears to fix it every time for me.
Here is my, very boilerplate, presentation code :
guard let type = UTType("com.my.type") else {
return
}
let fileBrowser = UIDocumentPickerViewController(forOpeningContentTypes: [type])
fileBrowser.overrideUserInterfaceStyle = .dark
fileBrowser.delegate = self
fileBrowser.directoryURL = myFileFolderURL()
self.present(fileBrowser, animated: true) {
Is there a recommended way on macOS 26 Tahoe to take a CoreAudio AudioObjectID and use it to lookup the underlying USB LocationID?
I previously used AudioObjectID to query the corresponding DeviceUID with kAudioDevicePropertyDeviceUID. Then I queried for the IOService matching kIOAudioEngineClassName with property kIOAudioEngineGlobalUniqueIDKey matching DeviceUID, and I loaded kUSBDevicePropertyLocationID from the result.
This fails on macOS 26, because the IO Registry for the device has an entry for usbaudiod rather than AppleUSBAudioEngine, and usbaudiod does not include a kIOAudioEngineGlobalUniqueIDKey property (or any other property to map it to a CoreAudio DeviceUID).
My use-case here is a piece of audio recording software that allows configuring a set of supported audio devices via USB HID prior to recording. I present the user with a list of CoreAudio devices to use, but without a way to lookup the underlying USB LocationID, I cannot guarantee that the configured device matches the selected device (e.g. if the user plugged in two identical microphones).
I'm trying to implement airplay into my app. I can successfully playback sound and trigger the airplay selector sheet. If the target device is a Bluetooth only device I can connect with no problem and stream the audio to the Bluetooth device, but if the audio device is a airplay specific device like a HomePod or an Apple TV when I select it, I get a spinning icon, indicating that it is trying to connect, and eventually it times out and stops without connecting.
I don't believe it is an AirPlay audio issue because if I go to a different app, for example a podcast app and select my HomePods for output, and then switch back to my app. My audio will correctly stream to the HomePod. Not only that, I have it so that my icon will change color to indicate that it is connected via airplay and it is correctly indicating that it is connected via AirPlay. But I cannot then disconnect it using the Airplay selector.
The issue appears to be in the AirPlay selection side, which I have spent several days attempting to troubleshoot mostly using ChatGPT to suggest code different than what I have to maybe work around the issue. Mostly it is focused on the audio player section, but it doesn't seem like that is really the route that is the problem.
My app encountered problems when trying to open an x86 audioUnit v2 on a Silicon Mac (although Rosetta is installed).
There seems to be a XPC connection issue with the AUHostingService that I don't know how to fix.
I observed other host apps opening the same plugins without problem, so there is probably something wrong or incompatible in my codes.
I noticed that:
The issue occurs whether or not the app is sandboxed.
The issue does no longer occur when the app itself runs under Rosetta.
There is no error reported by CoreAudio during allocation and initialization of the audio unit. The first notified errors appears when the unit calls AudioUnitRender from the rendering callback.
With most x86 plugins, the error is on first call:
kAudioUnitErr_RenderTimeout
and on any subsequent call:
kAudioComponentErr_InstanceInvalidated
On the UI side, when the Cocoa View is loaded, it appears shortly, then disappears immediately leaving its superview empty.
With another x86 plugin, the Cocoa View is loaded normally, but CoreAudio still emits
kAudioUnitErr_NoConnection
from AudioUnitRender, whether the view has been loaded or not, and the plugin produces no sound.
I also find these messages in the console (printed in that order):
CLIENT ERROR: RemoteAUv2ViewController does not override - and thus cannot react to catastrophic errors beyond logging them
AUAudioUnit_XPC.mm:641 Crashed AU possible component description: aumu/Helm/Tyte
My app uses the AUv2 API and I suspect that working with the AUv3 API would spare me these problems.
However, considering how my audio system is built (audio units are wrapped into C++ classes and most connections between units are managed on the fly from the rendering callback), it would be a lot of work to convert, and I’m even not sure that all I do with the AUv2 API would be possible with the AUv3 API.
I could possibly find an intermediate solution, but in the immediate future I'm looking for the simplest and fastest possible fix. If I cannot find better, I see two fallback options:
In this part of the doc: “Beginning with macOS 11, the system loads audio units into a separate process that depends on the architecture or host preference”, does “host preference” means that it would be possible to disable the “out of process” behavior, for example from the app entitlements or info.plist?
Otherwise, as a last resort, I could completely disable the use of x86 audioUnits when my app runs under ARM64, for at least making things cleaner. But the Audio Component API doesn’t give any info about the plugin architecture, how could I found it?
Any tip or idea about this issue will be much appreciated.
Thanks in advance!
I created a virtual audio device to capture system audio with a sample rate of 44.1 kHz. After capturing the audio, I forward it to the hardware sound card using AVAudioEngine, also with a sample rate of 44.1 kHz. However, due to the clock sources being unsynchronized, problems occur after a period of playback. How can I retrieve the clock source of the hardware device and set it for the virtual device?
Overview
We are producing audio in real time from an editing application and are trying to put that on an HLS stream. We attempt to submit PCM samples through an audio writer but are getting a crash after a select number of samples have been appended.
Depending on the number of audio frames in the PCM buffer, we might get more iterations before the crash but it always has the same traceback (see below).
Code
The setup is rather simple. We took inspiration from a few sources around the web.
NSMutableDictionary *audio = [[NSMutableDictionary alloc] init];
[audio setObject:@(kAudioFormatMPEG4AAC) forKey:AVFormatIDKey];
[audio setObject:[NSNumber numberWithInt:config.audioSampleRate] // 48000
forKey:AVSampleRateKey];
[audio setObject:[NSNumber numberWithInt:config.audioChannels] // 2
forKey:AVNumberOfChannelsKey];
[audio setObject:@160000 forKey:AVEncoderBitRateKey];
m_audioConfig = [[NSDictionary alloc] initWithDictionary:audio];
m_audio = [[AVAssetWriterInput alloc] initWithMediaType:AVMediaTypeAudio
outputSettings:m_audioConfig];
AVAudioFrameCount audioFrames = BUFFER_SAMPLES * bCount;
AVAudioPCMBuffer *pcmBuffer = [[AVAudioPCMBuffer alloc] initWithPCMFormat:m_full.pcmFormat
frameCapacity:audioFrames];
pcmBuffer.frameLength = pcmBuffer.frameCapacity;
AudioChannelLayout layout;
memset(&layout, 0, sizeof(layout));
layout.mChannelLayoutTag = kAudioChannelLayoutTag_Stereo;
CMFormatDescriptionRef format;
OSStatus stats = CMAudioFormatDescriptionCreate(
kCFAllocatorDefault,
pcmBuffer.format.streamDescription,
sizeof(layout),
&layout,
0,
nil,
nil,
&format
);
for (int i = 0; i < bCount; i++)
{
AudioPCM pcm;
audioCallback->callback(pcm);
memcpy(*(pcmBuffer.int16ChannelData) + (bufferSize * i), pcm.data, bufferSize);
}
size_t samplesConsumed = BUFFER_SAMPLES * bCount;
CMSampleBufferRef sampleBuffer;
CMSampleTimingInfo timing;
timing.duration = CMTimeMake(1, config.audioSampleRate);
timing.presentationTimeStamp = presentationTime;
timing.decodeTimeStamp = kCMTimeInvalid;
OSStatus ostatus = CMSampleBufferCreate(
kCFAllocatorDefault,
nil,
false,
nil,
nil,
format,
(CMItemCount)pcmBuffer.frameLength,
1,
&timing,
0,
nil,
&sampleBuffer
);
////
ostatus = CMSampleBufferSetDataBufferFromAudioBufferList(
sampleBuffer,
kCFAllocatorDefault,
kCFAllocatorDefault,
kCMSampleBufferFlag_AudioBufferList_Assure16ByteAlignment,
pcmBuffer.audioBufferList
);
if (ostatus != noErr)
{
NSLog(@"fill audio sample from buffer list failed: %s", logAudioError(ostatus));
return;
}
ostatus = CMSampleBufferSetDataReady(sampleBuffer);
if (ostatus != noErr)
{
NSLog(@"set sample buffer ready failed: %s", logAudioError(ostatus));
return;
}
// Finally we can attach it, then shove the presentation time forward
[m_audio appendSampleBuffer:sampleBuffer];
The Crash
The crash points towards some level of deallocation when the conversion tooling is done or has enough samples to process an output packet? It's had to say.
0 caulk 0x1a1e9532c caulk::alloc::tiered_allocator<caulk::alloc::size_range_tier<0ul, 1008ul, caulk::alloc::tree_allocator<caulk::alloc::chunk_allocator<caulk::alloc::page_allocator, caulk::alloc::bitmap_allocator, caulk::alloc::embed_block_memory, 16384ul, 16ul, 6ul>>>, caulk::alloc::size_range_tier<1009ul, 256000ul, caulk::alloc::guarded_edges_allocator<caulk::alloc::consolidating_free_map<caulk::alloc::page_allocator, 10485760ul>, 4ul>>, caulk::alloc::tracking_allocator<caulk::alloc::page_allocator>>::deallocate(caulk::alloc::block, unsigned long) + 636
1 AudioToolboxCore 0x1993fbfe4 ExtendedAudioBufferList_Destroy + 112
2 AudioToolboxCore 0x1993d5fe0 std::__1::__optional_destruct_base<ACCodecOutputBuffer, false>::~__optional_destruct_base[abi:ne180100]() + 68
3 AudioToolboxCore 0x1993d5f48 acv2::CodecConverter::~CodecConverter() + 196
4 AudioToolboxCore 0x1993d5e5c acv2::CodecConverter::~CodecConverter() + 16
5 AudioToolboxCore 0x1992574d8 std::__1::vector<std::__1::unique_ptr<acv2::AudioConverterBase, std::__1::default_delete<acv2::AudioConverterBase>>, std::__1::allocator<std::__1::unique_ptr<acv2::AudioConverterBase, std::__1::default_delete<acv2::AudioConverterBase>>>>::__clear[abi:ne180100]() + 84
6 AudioToolboxCore 0x199259acc acv2::AudioConverterChain::RebuildConverterChain(acv2::ChainBuildSettings const&) + 116
7 AudioToolboxCore 0x1992596ec acv2::AudioConverterChain::SetProperty(unsigned int, unsigned int, void const*) + 1808
8 AudioToolboxCore 0x199324acc acv2::AudioConverterV2::setProperty(unsigned int, unsigned int, void const*) + 84
9 AudioToolboxCore 0x199327f08 with_resolved(OpaqueAudioConverter*, caulk::function_ref<int (AudioConverterAPI*)>) + 60
10 AudioToolboxCore 0x1993281e4 AudioConverterSetProperty + 72
11 MediaToolbox 0x1a7566c2c FigSampleBufferProcessorCreateWithAudioCompression + 2296
12 MediaToolbox 0x1a754db08 0x1a70b5000 + 4819720
13 MediaToolbox 0x1a754dab4 FigMediaProcessorCreateForAudioCompressionWithFormatWriter + 100
14 MediaToolbox 0x1a77ebb98 0x1a70b5000 + 7564184
15 MediaToolbox 0x1a7804158 0x1a70b5000 + 7663960
16 MediaToolbox 0x1a7801da0 0x1a70b5000 + 7654816
17 AVFCore 0x1ada530c4 -[AVFigAssetWriterTrack addSampleBuffer:error:] + 192
18 AVFCore 0x1ada55164 -[AVFigAssetWriterAudioTrack _flushPendingSampleBuffersReturningError:] + 500
19 AVFCore 0x1ada55354 -[AVFigAssetWriterAudioTrack addSampleBuffer:error:] + 472
20 AVFCore 0x1ada4ebf0 -[AVAssetWriterInputWritingHelper appendSampleBuffer:error:] + 128
21 AVFCore 0x1ada4c354 -[AVAssetWriterInput appendSampleBuffer:] + 168
22 lib_devapple_hls.dylib 0x115d2c7cc detail::AppleHLSImplementation::audioRuntime() + 1052
23 lib_devapple_hls.dylib 0x115d2d094 void* std::__1::__thread_proxy[abi:ne180100]<std::__1::tuple<std::__1::unique_ptr<std::__1::__thread_struct, std::__1::default_delete<std::__1::__thread_struct>>, void (detail::AppleHLSImplementation::*)(), detail::AppleHLSImplementation*>>(void*) + 72
24 libsystem_pthread.dylib 0x196e5b2e4 _pthread_start + 136
Any insight would be welcome!
I'm getting this error when I launch my application on the iPhone 14 Pro via Xcode. Everything builds OK. I"m using the audio kit plugin and Sound Pipe Audiokit.
The error starts as soon as I start the app and will carry on repeatedly.
I have background processing turned on as I'd like the sounds to play when the phone is locked via the headphones.
I can't find anything online about this error. None of my catches are printing anything in the logs either. So I don't know if this is just something that pops up repeatedly or whether there is something fundamentally wrong.
private func setupAudioSession() {
do {
let session = AVAudioSession.sharedInstance()
try session.setCategory(.playback, mode: .default, options: [.mixWithOthers])
try session.setActive(true, options: .notifyOthersOnDeactivation)
} catch {
errorMessage = "Failed to set up audio session: (error.localizedDescription)"
print(errorMessage ?? "")
}
}
// MARK: - Background Task Handling
private func setupBackgroundTaskHandling() {
// Handle app entering background
notificationObservers.append(
NotificationCenter.default.addObserver(
forName: UIApplication.didEnterBackgroundNotification,
object: nil,
queue: .main,
using: { [weak self] _ in
// Safely unwrap self
guard let self = self else { return }
self.handleBackgroundTransition()
}
)
)
I'm not sure if this is the code causing the issue. Any help would be gratefully appreciated. This is my first app I'm working on .
Topic:
Media Technologies
SubTopic:
Audio
I have some tried-and-tested code that records and plays back audio via AUHAL which breaks on Tahoe on Intel. The same code works fine on Sequioa and also works on Tahoe on Apple Silicon.
To start with something simple, the following code to request access to the Microphone doesn't work as it should:
bool RequestMicrophoneAccess ()
{
__block AVAuthorizationStatus status =
[AVCaptureDevice authorizationStatusForMediaType: AVMediaTypeAudio];
if (status == AVAuthorizationStatusAuthorized)
return true;
__block bool done = false;
[AVCaptureDevice requestAccessForMediaType: AVMediaTypeAudio completionHandler: ^ (BOOL granted)
{
status = (granted) ? AVAuthorizationStatusAuthorized : AVAuthorizationStatusDenied;
done = true;
}];
while (!done)
CFRunLoopRunInMode (kCFRunLoopDefaultMode, 2.0, true);
return status == AVAuthorizationStatusAuthorized;
}
On Tahoe on Intel, the code runs to completion but granted is always returned as NO. Tellingly, the popup to ask the user to grant microphone access is never displayed, even though the app is not present in the Privacy pane and never appears there. On Apple Silicon, everything works fine.
There are some other problems, but I'm hoping they have a common underlying cause and that the Apple guys can figure out what's wrong from the information in this post. I'd be happy to test any potential fix. Thanks.
Topic:
Media Technologies
SubTopic:
Audio
I've got a web app built with MusicKit that displays a list of songs.
I have player controls for play, pause, skip next, skip, previous, toggle shuffle and set repeat mode.
All of these work by using music.
The play button, when nothing is playing and nothing is in the queue, will enqueue all the tracks and start playing with the below, for example:
await music.setQueue({ songs, startPlaying: true });
I've implemented a progress slider based on feedback from the "playbackProgressDidChange" listener.
Now, how in the world can I set the volume? This seems like it should be simple, but I am at a complete loss here.
The docs say:
"The volume of audio playback, which is set directly on the HTMLMediaElement as the HTMLMediaElement.volume property. This value ranges between 0, which would be muting the audio, and 1, which would be the loudest possible."
Given that all my controls work off the music instance, I don't understand how I can do that.
In this video from WWDC 2022, music web components are touched on briefly. These are also documented very sparsely. The volume docs are here.
For the life of me, I can't even get the volume web component to display in the UI.
It appears that MusicKit Web is hobbled compared to the native implementation, but surely adjusting volume shouldn't be that hard right?
I'd appreciate any insight on how to do this, including how to get web components to work (in a Next JS app).
Thanks.