We require assistance in resolving a critical audio design conflict within our Push-to-Talk (PTT) application. Our current volume amplification strategy—which relies on applying a GAIN factor to PCM samples in conjunction with setting the AVAudioSession category to Playback—is working successfully when PTT is used independently. However, upon integrating and reporting the same PTT call through the CallKit framework, this amplification effect is lost. The CallKit integration appears to be forcing a different, non-amplifying audio session category or configuration, negatively impacting the user's perceived call volume. We need guidance on how to maintain the AVAudioSessionCategoryPlayback setting, or an equivalent high-volume configuration, while operating under the control of CallKit.
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After upgrading to watchOS 26, users report that when playing music on Apple Watch, if a fitness reminder is received, the music automatically pauses and users need to manually tap the play button to resume music playback. This phenomenon occurs with multiple music and podcast apps.
This issue did not exist before the upgrade. We would like to know if this is an Apple bug or if there are any special development configurations needed?"
I have a new 2725QC (Dell) Monitor that uses USB-C connection to connect with the iMac (2019, 27 inch) through the back port but the problem is that the volume control can currently only be done from the hardware, not the software control using the Apple keyboard. What should I do in terms of writing code to do this (Swift or Obj-C)? Is there a third-party solution for Intel iMac and ARM Mac?
Hello,
I've discovered a buffer initialization bug in AVAudioUnitSampler that happens when loading presets with multiple zones referencing different regions in the same audio file (monolith/concatenated samples approach).
Almost all zones output silence (i.e. zeros) at the beginning of playback instead of starting with actual audio data.
The Problem
Setup:
Single audio file (monolith) containing multiple concatenated samples
Multiple zones in an .aupreset, each with different sample start and sample end values pointing to different regions of the same file
All zones load successfully without errors
Expected Behavior:
All zones should play their respective audio regions immediately from the first sample.
Actual Behavior:
Last zone in the zone list: Works perfectly - plays audio immediately
All other zones: Output [0, 0, 0, 0, ..., _audio_data] instead of [real_audio_data]
The number of zeros varies from event to event for each zone. It can be a couple of samples (<30) up to several buffers.
After the initial zeros, the correct audio plays normally, so there is no shift in audio playback, just missing samples at the beginning.
Minimal Reproduction
1. Create Test Monolith Audio File
Create a single Wav file with 3 concatenated 1-second samples (44.1kHz):
Sample 1: frames 0-44099 (constant amplitude 0.3)
Sample 2: frames 44100-88199 (constant amplitude 0.6)
Sample 3: frames 88200-132299 (constant amplitude 0.9)
2. Create Test Preset
Create an .aupreset with 3 zones all referencing the same file:
Pseudo code
<Zone array>
<zone 1> start : 0, end: 44099, note: 60, waveform: ref_to_monolith.wav;
<zone 2> start sample: 44100, note: 62, end sample: 88199, waveform: ref_to_monolith.wav;
<zone 3> start sample: 88200, note: 64, end sample: 132299, waveform: ref_to_monolith.wav;
</Zone array>
3. Load and Test
// Load preset into AVAudioUnitSampler
let sampler = AVAudioUnitSampler()
try sampler.loadAudioFiles(from: presetURL)
// Play each zone (MIDI notes C4=60, D4=62, E4=64)
sampler.startNote(60, withVelocity: 64, onChannel: 0) // Zone 1
sampler.startNote(62, withVelocity: 64, onChannel: 0) // Zone 2
sampler.startNote(64, withVelocity: 64, onChannel: 0) // Zone 3
4. Observed Result
Zone 1 (C4): [0, 0, 0, ..., 0.3, 0.3, 0.3] ❌ Zeros at beginning
Zone 2 (D4): [0, 0, 0, ..., 0.6, 0.6, 0.6] ❌ Zeros at beginning
Zone 3 (E4): [0.9, 0.9, 0.9, ...] ✅ Works correctly (last zone)
What I've Extensively Tested
What DOES Work
Separate files per zone:
Each zone references its own individual audio file
All zones play correctly without zeros
Problem: Not viable for iOS apps with 500+ sample libraries due to file handle limitations
What DOESN'T Work (All Tested)
1. Different Audio Formats:
CAF (Float32 PCM, Int16 PCM, both interleaved and non-interleaved)
M4A (AAC compressed)
WAV (uncompressed)
SF2 (SoundFont2)
Bug persists across all formats
2. CAF Region Chunks:
Created CAF files with embedded region chunks defining zone boundaries
Set zones with no sampleStart/sampleEnd in preset (nil values)
AVAudioUnitSampler completely ignores CAF region metadata
Bug persists
3. Unique Waveform IDs:
Gave each zone a unique waveform ID (268435456, 268435457, 268435458)
Each ID has its own file reference entry (all pointing to same physical file)
Hypothesized this might trigger separate buffer initialization
Bug persists - no improvement
4. Different Sample Rates:
Tested: 44.1kHz, 48kHz, 96kHz
Bug occurs at all sample rates
5. Mono vs Stereo:
Bug occurs with both mono and stereo files
Environment
macOS: Sonoma 14.x (tested across multiple minor versions)
iOS: Tested on iOS 17.x with same results
Xcode: 16.x
Frameworks: AVFoundation, AudioToolbox
Reproducibility: 100% reproducible with setup described above
Impact & Use Case
This bug severely impacts professional music applications that need:
Small file sizes: Monolith files allow sharing compressed audio data (AAC/M4A)
iOS file handle limits: Opening 400+ individual sample files is not viable on iOS
Performance: Single file loading is much faster than hundreds of individual files
Standard industry practice: Monolith/concatenated samples are used by EXS24, Kontakt, and most professional samplers
Current Impact:
Cannot use monolith files with AVAudioUnitSampler on iOS
Forced to choose between: unusable audio (zeros at start) OR hitting iOS file limits
No viable workaround exists
Root Cause Hypothesis
The bug appears to be in AVAudioUnitSampler's internal buffer initialization when:
Multiple zones share the same source audio file
Each zone specifies different sampleStart/sampleEnd offsets
Key observation: The last zone in the zone array always works correctly.
This is NOT related to:
File permissions or security-scoped resources (separate files work fine)
Audio codec issues (happens with uncompressed PCM too)
Preset parsing (preset loads correctly, all zones are valid)
Questions
Is this a known issue? I couldn't find any documentation, bug reports, or discussions about this.
Is there ANY workaround that allows monolith files to work with AVAudioUnitSampler?
Alternative APIs? Is there a different API or approach for iOS that properly supports monolith sample files?
I have the new iOS 26 SpeechTranscriber working in my application. The issue I am facing is how to determine if the device I am running on supports SpeechTranscriber. I was able to create code that tests if the device supports transcription but it takes a bit of time to run and thus the results are not available when the app launches. What I am looking for is a list of what iOS 26 devices it doesn't run on. I think its safe to assume any new devices will support it so if we can just have a list of what devices that can run iOS 26 and not able to do transcription it would be much faster for the app. I have determined it doesn't work on a SE 2nd Gen, it works on iPhone 12, SE 3rd Gen, iPhone 14 Pro, 15 Pro. As the SpeechTranscriber doesn't work in the simulator I can't determine that way. I have checked the docs and it doesn't list the devices it doesn't work on.
Hi,
I'm still stuck getting a basic record-with-playthrouh pipeline to work.
Has anyone a sample of setting up a AVAudioEngine pipeline for recording with playthrough?
Plkaythrough works with AVPlayerNode as input but not with any microphone input. The docs mention the "enabled state" of the outputNode of the engine without explaining the concept, i.e. how to enable an output.
When the engine renders to and from an audio device, the AVAudioSession category and the availability of hardware determines whether an app performs output. Check the output node’s output format (specifically, the hardware format) for a nonzero sample rate and channel count to see if output is in an enabled state.
Well, in my setup the output is NOT enabled, and any attempt to switch (e.g. audioEngine.outputNode.auAudioUnit.setDeviceID(deviceID) )/ attach a dedicated device / ... results in exceptions / errors
Hi,
I am creating an app that can include videos or images in it's data. While
@Attribute(.externalStorage)
helps with images, with AVAssets I actually would like access to the URL behind that data. (as it would be stupid to load and then save the data again just to have a URL)
One key component is to keep all of this clean enough so that I can use (private) CloudKit syncing with the resulting model.
All the best
Christoph
I am trying to stream audio from local filesystem.
For that, I am trying to use an AVAssetResourceLoaderDelegate for an AVURLAsset. However, Content-Length is not known at the start. To overcome this, I tried several methods:
Set content length as nil, in the AVAssetResourceLoadingContentInformationRequest
Set content length to -1, in the ContentInformationRequest
Both of these cause the AVPlayerItem to fail with an error.
I also tried setting Content-Length as INT_MAX, and setting a renewalDate = Date(timeIntervalSinceNow: 5). However, that seems to be buggy. Even after updating the Content-Length to the correct value (e.g. X bytes) and finishing that loading request, the resource loader keeps getting requests with requestedOffset = X with dataRequest.requestsAllDataToEndOfResource = true. These requests keep coming indefinitely, and as a result it seems that the next item in the queue does not get played. Also, .AVPlayerItemDidPlayToEndTime notification does not get called.
I wanted to check if this is an expected behavior or is there a bug in this implementation. Also, what is the recommended way to stream audio of unknown initial length from local file system?
Thanks!
Your draft looks great! Here's a refined version with the iOS 17 comparison emphasized and slightly better flow:
Hi Apple Engineers and fellow developers,
I'm experiencing a critical regression with ShazamKit's background operation on iOS 18. ShazamKit's SHManagedSession stops identifying songs in the background after approximately 20 seconds on iOS 18, while the exact same code works perfectly on iOS 17.
The behavior is consistent: the app works perfectly in the foreground, but when backgrounded or device is locked, it initially works for about 20 seconds then stops identifying new songs. The microphone indicator remains active suggesting audio access is maintained, but ShazamKit doesn't send identified songs in the background until you open the app again. Detection immediately resumes when bringing the app to foreground.
My technical setup uses SHManagedSession for continuous matching with background modes properly configured in Info.plist including audio mode, and Background App Refresh enabled. I've tested this on physical devices running iOS 18.0 through 18.5 with the same results across all versions. The exact same code running on iOS 17 devices works flawlessly in the background.
To reproduce: initialize SHManagedSession and start matching, begin song identification in foreground, background the app or lock device, play different songs which are initially detected for about 20 seconds, then after the timeout period new songs are no longer identified until you bring the app to foreground.
This regression has impacted my production app as users who rely on continuous background music identification are experiencing a broken feature. I submitted this as Feedback ID FB15255903 last September with no solution so far.
I've created a minimal demo project that reproduces this issue: https://github.com/tfmart/ShazamKitBackground
Has anyone else experienced this ShazamKit background regression on iOS 18? Are there any known workarounds or alternative approaches? Given the time this issue has persisted, could we please get acknowledgment of this regression, expected timeline for a fix, or any recommended workarounds?
Testing environment is Xcode 16.0+ on iOS 18.0-18.5 across multiple physical device models.
Any guidance would be greatly appreciated.
I'm developing the VisionOS app. I want to know how to play spatial audio in addition to RealityKit? If it's iOS or macOS, how to play spatial audio in addition to RealityKit?
I’m working on a macOS app, written in Swift. My goal is to record audio from an external microphone, e.g., one connected via USB.
For this, I’m using an AVCaptureSession and recording its output with an AVAssetWriter. This works perfectly in principle (and reliably with internal microphones, for example).
The problem occurs after my app has successfully completed the first recording and I then want to make additional recordings (which makes me think it might be process-dependent, because it works again after restarting the app).
The problem: Noisy or distorted-sounding audio files. In addition, the following error message appears in the Console from CoreAudio / its AudioConverter:
Input data proc returned inconsistent 512 packets for 2048 bytes; at 3 bytes per packet, that is actually 682 packets
It is easy to reproduce. This problem is reproducible even if I don’t configure the AVAssetWriter manually and instead let it receive its audioSettings using a preset from an AVOutputSettingsAssistant. I’m running on macOS 15.0 (24A335).
I’ve filed a feedback including a demo project → FB15333298 🎟️
I would greatly appreciate any help!
Have a great day,
Martin
Hi,
I am looking for a good way to play sounds at a high frequency.
At the moment I am using the AVAudioEngine, and create a couple AVAudioPlayerNode and for each sound I need to play I create a AVAudioPCMBuffer.
When the app needs to play a sound, I get the correct AVAudioPCMBuffer for the sound and use the first available AVAudioPlayerNode and feed it to the buffer.
The timing for a metronome app has to be very precise because if it's of by about 16ms the user can hear that it is not playing had the right interval. For low speeds this is working without any problems, but at high speeds it is getting worse.
Maybe anyone has an idea on how I can improve my method.
Its a Plugin for Flutter.
import AVFoundation
class FastSoundPlayer {
private var audioPlayers: [SoundPlayer?] = []
private var sounds: [String: Sound] = [:]
private var engine = AVAudioEngine()
let session = AVAudioSession.sharedInstance()
init() {
do {
try session.setCategory(AVAudioSession.Category.playback, mode: AVAudioSession.Mode.default, options: [AVAudioSession.CategoryOptions.mixWithOthers])
try session.setActive(true)
createSoundPlayers(count: 20)
try engine.start()
} catch {
print("Error starting audio engine: \(error.localizedDescription)")
}
}
// Selector method to handle applicationDidBecomeActiveNotification
func applicationDidBecomeActive() {
// Reinitialize AVAudioEngine and reattach all nodes
do {
engine.reset()
objc_sync_enter(audioPlayers)
audioPlayers.removeAll()
createSoundPlayers(count: 20)
objc_sync_exit(audioPlayers)
try engine.start()
} catch {
print("Error starting audio engine: \(error.localizedDescription)")
}
}
func createSoundPlayers(count: Int) {
for _ in 0..<count {
let player = SoundPlayer()
engine.attach(player.player)
engine.connect(player.player, to: engine.mainMixerNode, format: nil)
audioPlayers.append(player)
}
}
func load(sound: Data, name: String) {
let sound = Sound(soundData: sound)
sounds[name] = sound
}
func play(name: String) {
if !engine.isRunning {
applicationDidBecomeActive()
}
guard let sound = sounds[name] else {
print("Sound not found")
return
}
if let player = getAvailablePlayer() {
player.play(sound: sound)
}
}
func getAvailablePlayer() -> SoundPlayer? {
for player in audioPlayers {
if !player!.isPlaying {
return player
}
}
return nil
}
}
class SoundPlayer {
let player = AVAudioPlayerNode()
var isPlaying = false
init() {
player.volume = 1.0
}
func play(sound: Sound) {
player.scheduleBuffer(sound.sound!, at: nil, options: .interrupts, completionCallbackType: .dataPlayedBack) { _ in
self.complete()
}
if (player.engine != nil && player.engine!.isRunning) {
player.play()
isPlaying = true
}
}
func complete() {
isPlaying = false
}
}
class Sound {
var sound: AVAudioPCMBuffer?
init(soundData: Data) {
do {
let temporaryURL = FileManager.default.temporaryDirectory.appendingPathComponent("tempSound.wav")
try soundData.write(to: temporaryURL)
// Create AVAudioFile from the temporary file URL
let audioFile = try AVAudioFile(forReading: temporaryURL)
// Define the format for the PCM buffer (44100Hz, stereo)
let format = AVAudioFormat(commonFormat: .pcmFormatInt16, sampleRate: 44100, channels: 2, interleaved: false)
// Create AVAudioPCMBuffer
guard let pcmBuffer = AVAudioPCMBuffer(pcmFormat: format!, frameCapacity: AVAudioFrameCount(audioFile.length)) else {
// Failed to create PCM buffer
self.sound = nil
return
}
// Read audio file into PCM buffer
try audioFile.read(into: pcmBuffer)
// Assign the created AVAudioPCMBuffer to the sound property
self.sound = pcmBuffer
} catch {
print("Error loading sound file: \(error.localizedDescription)")
self.sound = nil
}
}
}
Thanks!
Hi I'm new to the forum,
I'm planning an app just for Apple watch, I would like to use bluetooth audio in background, how can I do it?
The messages I send via bluetooth stop as soon as the watch display turns off.
Thank you!
Nax
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.
Songs can be unavailable (greyed out) in Apple Music. How can I check if a song is unavailable via the MusicKit framework? Obviously the playback will fail with MPMusicPlayerControllerErrorDomain Code=6 "Failed to prepare to play" but how can I know that in advance? I need to check the availability of hundreds of albums and therefore initiating a playback for each of them is not an option.
Things I have tried:
Checking if the release date property is set to a future date. This filters out all future releases but doesn't solve the problem for already released songs.
Checking if the duration is 0. This does not work since the duration of unavailable songs does not have to be 0.
Initiating a playback and checking for the "Failed to prepare to play" error. This is not suitable for a huge amount of Albums.
I couldn't find a solution yet but somehow other third-party-apps are able ignore/don't shows these albums. I believe the Apple Music app is only displaying albums where at least one song is available.
I am using this function to fetch all albums of an artist.
private func fetchAlbumsFor(_ artist: Artist) async throws -> [Album] {
let artistWithAlbums = try await artist.with(.albums)
var allAlbums = [Album]()
guard var currentBadge = artistWithAlbums.albums else {
return []
}
allAlbums.append(contentsOf: currentBadge)
while currentBadge.hasNextBatch {
if let nextBatch = try await currentBadge.nextBatch() {
currentBadge = nextBatch
allAlbums.append(contentsOf: nextBatch)
} else {
break
}
}
return allAlbums
}
Here is an example album where I am unable to detect its unavailability (at least in Germany):
https://music.apple.com/de/album/die-haferhorde-immer-den-n%C3%BCstern-nach-h%C3%B6rspiel-zu-band-3/1755774804
Furthermore I was unable to navigate to this album via the Apple Music app directly.
Thanks for any help
Edit: Apparently this album is not included in an apple music subscription but can be bought seperately. The question remains: How can I check that?
I have a SwiftUI app - (https://youtu.be/VbAfUk_eYl0?si=JxUBh0Bpb-vc1E1U) - which I thought was almost ready for release - a manager for airdropped audio files from Logic Pro or other music creation applications. It uses AVAudioEngine and AVAudioPlayerNode to play audio, and the MediaPlayer API to integrate with car audio and similar, all of which works well.
It does not currently have an explicit CarPlay integration (and I'm slightly horrified at the amount of work that is going to require).
I had the good or bad luck of getting a loaner car with carplay while mine is being repaired yesterday, and lo and behold, when connected to the vehicle via CarPlay, there is no audio output in the vehicle at all. The now playing panel correctly shows the information my app provides about the currently playing song; the player node believes it is playing, the AVAudioSession is configured as it should be. But there is no sound.
Obviously I cannot ship it in this state.
I've tried fiddling with the parameters the AVAudioSession is configured with, in case there was some parameter that was preventing audio output, to no avail - currently:
var options = AVAudioSession.CategoryOptions()
options.insert(.allowAirPlay)
options.insert(.allowBluetooth)
options.insert(.allowBluetoothA2DP)
try session.setCategory(.playback, mode: .default, options: options)
try? session.setPreferredIOBufferDuration(0.002) // ~96 samples at 44.1kHz
try? session.setPrefersNoInterruptionsFromSystemAlerts(true)
try? session.setPrefersInterruptionOnRouteDisconnect(false)
try session.setActive(true, options: [.notifyOthersOnDeactivation])
All diagnostics within the app show the player operating correctly - files are played and flushed; AVAudioPlayerNodeCompletionCallbacks are called when they should be. But the output is not audible in the vehicle.
I would much prefer to ship this app without full-blown CarPlay integration, but with working audio when connected via CarPlay, and work on full CarPlay integration for the next release.
Is there some secret handshake I am just missing to make this work?
Here is the demo from Apple's site
This issues is specific to iOS 18.
When running this demo, we are getting new text when we have a gap in speaking, the recognitionTask(with:resultHandler:) provides new text which is only spoken after the gap and not the concatenation of old text and the new spoken text.
I might have misunderstood the docs, but is Call Translation going to be available for VOIP applications? Eg in an already connected VOIP call, would it be possible for Call Translations to be enabled on an iOS 26 and Apple Intelligence supported device?
I have personally tried it and it doesn’t look like it supported VOIP but would love to confirm this.
reference: https://developer.apple.com/documentation/callkit/cxsettranslatingcallaction/
Topic:
Media Technologies
SubTopic:
Audio
I have a PCM audio buffer (AVAudioPCMFormatInt16). When I try to play it using AVPlayerNode / AVAudioEngine an exception is thrown:
"[[busArray objectAtIndexedSubscript:(NSUInteger)element] setFormat:format error:&nsErr]: returned false, error Error Domain=NSOSStatusErrorDomain Code=-10868
(related thread https://forums.developer.apple.com/forums/thread/700497?answerId=780530022#780530022)
If I convert the buffer to AVAudioPCMFormatFloat32 playback works.
My questions are:
Does AVAudioEngine / AVPlayerNode require AVAudioPCMBuffer to be in the Float32 format? Is there a way I can configure it to accept another format instead for my application?
If 1 is YES is this documented anywhere?
If 1 is YES is this required format subject to change at any point?
Thanks!
I was looking to watch the "AVAudioEngine in Practice" session video from WWDC 2014 but I can't find it anywhere (https://forums.developer.apple.com/forums/thread/747008).
So I'm using AVAudioEngine. When playing audio I become the 'now playing' app using MPNowPlayingInfoCenter/MPRemoteCommandCenter APIs.
When configuring MPRemoteCommandCenter I add a play/pause command target via -addTargetWithHandler on the togglePlayPauseCommand property.
Now I also have a play/pause button in my app's UI. When I pause playback from my app's UI (which means I'm the active app, I'm in the foreground), what I do is this:
-I pause the AVAudioPlayerNode I'm using with AVAudioEngine.
I do not, stop, reset, etc. the AVAudioEngine. I only pause the player node. My thought process here is that the user just pressed pause and it is very likely that he will hit 'play' to resume playback in the near future because
My app is in the foreground and the user just hit the pause button.
Now if my app moves to the background and if I receive a memory warning I presume it'd make sense to tear down the engine or pause it. Perhaps I'm wrong about this?
So when I initially hit the play button from my app's UI I also activate my AVAudioSession. I do this in high priority NSOperation since the documentation warns that "we recommend that applications not activate their session from a thread where a long blocking operation will be problematic."
So now I'm playing and I hit pause from my app's UI. Then I quickly bring up the "Now Playing" center and I see I'm the "Now Playing" app but the play-pause button is showing the pause icon instead of the play icon but I'm in the pause state. I do set MPNowPlayingInfoCenter's playbackState to MPNowPlayingPlaybackStatePaused when I pause. Not surprisingly this doesn't work. The documentation states this is for macOS only.
So the only way to get MPRemoteCommandCenter to show the "play" image for the play-pause button is to deactivate my AVAudioSession when I pause playback? Since I change the active state of my audio session in a NSOperation because documentation recommends "we recommend that applications not activate their session from a thread where a long blocking operation will be problematic." the play-pause toggle in the remote command center won't immediately update since I'm doing it on another thread.
IMO it feels kind of inappropriate for a play-pause button to wait on a NSOperation activating the audio session before updating its UI when I already know my play/paused state, it should update right away like the button in my app does. Wouldn't it be nicer to just use MPNowPlayingInfoCenter's playbackState property on iOS too? If I'm no the longer the now playing app/active audio session it doesn't matter since I'm not in the now playing UI, just ignore it?
Also is it recommended that I deactivate my audio session explicitly every time the user pauses audio in my app (when I'm in the foreground)?
Also when I do deactivate the audio session I get an error: AVAudioSessionErrorCodeIsBusy (but the button in the now playing center updates to the proper image). I do this :
-(void)pause
{
[self.playerNode pause];
[self runOperationToDeactivateAudioSession];
// This does nothing on iOS:
MPNowPlayingInfoCenter *nowPlayingCenter = [MPNowPlayingInfoCenter defaultCenter];
nowPlayingCenter.playbackState = MPNowPlayingPlaybackStatePaused;
}
So in -runOperationToDeactivateAudioSession I get the AVAudioSessionErrorCodeIsBusy. According to the documentation
Starting in iOS 8, if the session has running I/Os at the time that deactivation is requested, the session will be deactivated, but the method will return NO and populate the NSError with the code property set to AVAudioSessionErrorCodeIsBusy to indicate the misuse of the API.
So pausing the player node when pausing isn't enough to meet the deactivation criteria. I guess I have to pause or stop the audio engine. I could probably wait until I receive a scene went to background notification or something before deactivating my audio session (which is async, so the button may not update to the correct image in time). This seems like a lot of code to have to write to get a play-pause toggle to update, especially in iPad-multi window scene environment.
What's the recommended approach?
Should I pause the AudioEngine instead of the player node always?
Should I always explicitly deactivate my audio session when the user pauses playback from my app's UI even if I'm in the foreground?
I personally like the idea of just being able to set
[MPNowPlayingInfoCenter defaultCenter].playbackState = MPNowPlayingPlaybackStatePaused;
But maybe that's because that would just make things easier on me. This does feels overcomplicated though. If anyone can share some tips on how I should handle this, I'd appreciate it.