Hello everyone,
I’m new to Swift development and have been working on an audio module that plays a specific sound at regular intervals - similar to a workout timer that signals switching exercises every few minutes.
Following AVFoundation documentation, I’m configuring my audio session like this:
let session = AVAudioSession.sharedInstance()
try session.setCategory(
.playback,
mode: .default,
options: [.interruptSpokenAudioAndMixWithOthers, .duckOthers]
)
self.engine.attach(self.player)
self.engine.connect(self.player, to: self.engine.outputNode, format: self.audioFormat)
try? session.setActive(true)
When it’s time to play cues, I schedule playback on a DispatchQueue:
// scheduleAudio uses DispatchQueue
self.scheduleAudio(at: interval.start) {
do {
try audio.engine.start()
audio.node.play()
for sample in interval.samples {
audio.node.scheduleBuffer(sample.buffer, at: AVAudioTime(hostTime: sample.hostTime))
}
} catch {
print("Audio activation failed: \(error)")
}
}
This works perfectly in the foreground. But once the app goes into the background, the scheduled callback runs, yet the audio engine fails to start, resulting in an error with code 561015905.
Interestingly, if the app is already playing audio before going to the background, the scheduled sounds continue to play as expected.
I have added the required background audio mode to my Info plist file by including the key UIBackgroundModes with the value audio.
Is there anything else I should configure? What is the best practice to play periodic audio when the app runs in the background? How do apps like turn-by-turn navigation handle continuous audio playback in the background?
Any advice or pointers would be greatly appreciated!
Audio
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Hi,
Not sure if this is the right forum to ask this question in, but could you please advise if I can use Apple Digital Masters logo (badge) in my iOS app that is playing music from Apple Music service?
Topic:
Media Technologies
SubTopic:
Audio
Since MacOS 26 Apple Music has inconsitent drops to the Quality of some Tracks indiscrimantly. I don't know if others Expereinced it. It doesn't happen on the Speakers or connected via Bluetooth, but the AUX I/O has it quite often. It is more noticable on Headphones with 48kHz and higher Frequency Bandwidth.
Here is the FB18062589
If I call AudioDeviceStart on an AudioDevice in my application then "Hey Siri!" will not wake Siri up. Our users have complained that Siri does not get activated with my application is running. We found that calling AudioDeviceStart is causing the issue.
How should we handle this?
I'm trying to implement Ambisonic B-Format audio playback on Vision Pro with head tracking. So far audio plays, head tracking works, and the sound appears to be stereo. The problem is that it is not a proper binaural playback when compared to playing back the audiofile with a DAW. Has anyone successfully implemented B-Format playback on Vision Pro? Any suggestions on my current implementation:
func playAmbiAudioForum() async {
do {
try AVAudioSession.sharedInstance().setCategory(.playback)
try AVAudioSession.sharedInstance().setActive(true)
// AudioFile laoding/preperation
guard let testFileURL = Bundle.main.url(forResource: "audiofile", withExtension: "wav") else {
print("Test file not found")
return
}
let audioFile = try AVAudioFile(forReading: testFileURL)
let audioFileFormat = audioFile.fileFormat
// create AVAudioFormat with Ambisonics B Format
guard let layout = AVAudioChannelLayout(layoutTag: kAudioChannelLayoutTag_Ambisonic_B_Format) else {
print("layout failed")
return
}
let format = AVAudioFormat(
commonFormat: audioFile.processingFormat.commonFormat,
sampleRate: audioFile.fileFormat.sampleRate,
interleaved: false,
channelLayout: layout
)
// write audiofile to buffer
guard let buffer = AVAudioPCMBuffer(pcmFormat: format, frameCapacity: UInt32(audioFile.length)) else {
print("buffer failed")
return
}
try audioFile.read(into: buffer)
playerNode.renderingAlgorithm = .HRTF
// connecting nodes
audioEngine.attach(playerNode)
audioEngine.connect(playerNode, to: audioEngine.outputNode, format: format)
audioEngine.prepare()
playerNode.scheduleBuffer(buffer, at: nil) {
print("File finished playing")
}
try audioEngine.start()
playerNode.play()
} catch {
print("Setup error:", error)
}
}
I have sent in a feedback report (FB18222398) but I have no idea if anyone has looked at it. I know from past experiences that Apple devs do look at these forums.
This applies to each of the betas, 1, 2 and 3. I have created a new Personal Voice with each beta. I create a personal voice in English. When it's done processing, I tap Preview and it says in English what is expected. But after some time, an hour or a day, the language of the voice file changes languages and no longer works properly. If I press Preview it is no longer intelligible. I have a text to speech app and initially the created voice works but then when the language of the file changes, it no longer works. I have run an app on my iphone through Xcode that prints to the console the voices installed on the device with the language. Currently this is the voice file:
Voice Identifier: com.apple.speech.personalvoice.AAA9C6F2-9125-475F-BA2F-22C63274991D
Language: es-MX
and on a second device the same personal voice is in a different language:
Voice Identifier: com.apple.speech.personalvoice.AAA9C6F2-9125-475F-BA2F-22C63274991D
Language: zh-CN
Although, a previous personal voice file that listed as Spanish-Mexican played in English with a Spanish accent or when playing Spanish text, it sounded almost perfect. This current personal voice doesn't do that, and is unintelligible. Previous attempts have converted to Chinese.
I hope someone can look into this.
Since the last update to IOS 26.0 (23A5276f) the AirPods connect to my IPhone and the Audio is still running through the phone. They are shown in the Bluetooth Icon that they’re paired.
Topic:
Media Technologies
SubTopic:
Audio
hi,
i need to read wether the transport is playing or stopped but my current method that works for vst does not work for au.
is there a lpx resource available for developers anywhere?
if (auto* playHead = processor->getPlayHead())
{
juce::AudioPlayHead::CurrentPositionInfo posInfo;
if (playHead->getCurrentPosition(posInfo))
{
bool isCurrentlyPlaying = posInfo.isPlaying;
if (isCurrentlyPlaying != wasTransportPlaying)
{
if (isCurrentlyPlaying)
{
wasTransportPlaying = isCurrentlyPlaying;
startAllTimers();
}
else
{
wasTransportPlaying = isCurrentlyPlaying;
stopAllTimers();
}
}
}
}
thanks :)
Hello. My app uses AVAudioRecorder to generate recording files, which are consistently only 4kb in size. Most users generate audio files normally, with only a few users experiencing this phenomenon occasionally. After uninstalling and installing the app, it will work normally, but it will reappear after a period of time. I have compared that the problematic audio files generated each time are fixed and cannot be played. Added the audioRecorderDidFinishRecording proxy method, which shows that the recording was completed normally. The user also reported that the recording is normal, but there is a problem with the generated file. How should I handle this issue? Look forward to your reply.
- (void)startRecordWithOrderID:(NSString *)orderID {
AVAudioSession *audioSession = [AVAudioSession sharedInstance];
[audioSession setCategory:AVAudioSessionCategoryRecord error:nil];
[audioSession setActive:YES error:nil];
NSMutableDictionary *settings = [[NSMutableDictionary alloc] init];
[settings setObject:[NSNumber numberWithFloat: 8000.0] forKey:AVSampleRateKey];
[settings setObject:[NSNumber numberWithInt: kAudioFormatLinearPCM] forKey:AVFormatIDKey];
[settings setObject:[NSNumber numberWithInt:16] forKey:AVLinearPCMBitDepthKey];
[settings setObject:[NSNumber numberWithInt: 1] forKey:AVNumberOfChannelsKey];
[settings setObject:[NSNumber numberWithBool:NO] forKey:AVLinearPCMIsBigEndianKey];
[settings setObject:[NSNumber numberWithBool:NO] forKey:AVLinearPCMIsFloatKey];
NSString *path = [WDUtility createDirInDocument:@"audios" withOrderID:orderID withPathExtension:@"wav"];
NSURL *tmpFile = [NSURL fileURLWithPath:path];
recorder = [[AVAudioRecorder alloc] initWithURL:tmpFile settings:settings error:nil];
[recorder setDelegate:self];
[recorder prepareToRecord];
[recorder record];
}
Let's consider the following code.
I've created an actor that loads a list of .mp3 files from a Bundle and then makes it available for audio reproduction.
Unfortunately, I'm experiencing a memory leak.
At the play method.
player.play()
From Instruments I get
_malloc_type_malloc_outlined libsystem_malloc.dylib
start_wqthread libsystem_pthread.dylib
private actor AudioActor {
enum Failure: Error {
case soundsNotLoaded([AudioPlayerClient.Sound: Error])
}
enum Player {
case music(AVAudioPlayer)
}
var players: [Sound: Player] = [:]
let bundles: [Bundle]
init(bundles: UncheckedSendable<[Bundle]>) {
self.bundles = bundles.wrappedValue
}
func load(sounds: [Sound]) throws {
try AVAudioSession.sharedInstance().setActive(true, options: [])
var errors: [Sound: Error] = [:]
for sound in sounds {
guard let url = bundle.url(forResource: sound.name, withExtension: "mp3")
else { continue }
do {
self.players[sound] = try .music(AVAudioPlayer(contentsOf: url))
} catch {
errors[sound] = error
}
}
guard errors.isEmpty
else { throw Failure.soundsNotLoaded(errors) }
}
func play(sound: Sound, loops: Int?) throws {
guard let player = self.players[sound]
else { return }
switch player {
case let .music(player):
player.numberOfLoops = loops ?? -1
player.play()
}
}
func stop(sound: Sound) throws {
guard let player = self.players[sound]
else { throw Failure.soundsNotLoaded([:]) }
switch player {
case let .music(player):
player.stop()
}
}
}
It sounds simple but searching for the name "Favorite Songs" is a non-starter because it's called different names in different countries, even if I specify "&l=en_us" on the query.
So is there another property, relationship or combination thereof which I can use to tell me when I've found the right playlist?
Properties I've looked at so far:
canEdit: will always be false so narrows things down a little
inFavorites: not helpful as it depends on whether the user has favourite the favourites playlist, so not relevant
hasCatalog: seems always true so again may narrow things down a bit
isPublic: doesn't help
Adding the catalog relationship doesn't seem to show anything immediately useful either.
Can anyone help?
Ideally I'd like to see this as a "kind" or "type" as it has different properties to other playlists, but frankly I'll take anything at this point.
I’m facing a problem while trying to achieve spatial audio effects in my iOS 18 app. I have tried several approaches to get good 3D audio, but the effect never felt good enough or it didn’t work at all.
Also what mostly troubles me is I noticed that AirPods I have doesn’t recognize my app as one having spatial audio (in audio settings it shows "Spatial Audio Not Playing"). So i guess my app doesn't use spatial audio potential.
First approach uses AVAudioEnviromentNode with AVAudioEngine. Chaining position of player as well as changing listener’s doesn’t seem to change anything in how audio plays.
Here's simple how i initialize AVAudioEngine
import Foundation
import AVFoundation
class AudioManager: ObservableObject {
// important class variables
var audioEngine: AVAudioEngine!
var environmentNode: AVAudioEnvironmentNode!
var playerNode: AVAudioPlayerNode!
var audioFile: AVAudioFile?
...
//Sound set up
func setupAudio() {
do {
let session = AVAudioSession.sharedInstance()
try session.setCategory(.playback, mode: .default, options: [])
try session.setActive(true)
} catch {
print("Failed to configure AVAudioSession: \(error.localizedDescription)")
}
audioEngine = AVAudioEngine()
environmentNode = AVAudioEnvironmentNode()
playerNode = AVAudioPlayerNode()
audioEngine.attach(environmentNode)
audioEngine.attach(playerNode)
audioEngine.connect(playerNode, to: environmentNode, format: nil)
audioEngine.connect(environmentNode, to: audioEngine.mainMixerNode, format: nil)
environmentNode.listenerPosition = AVAudio3DPoint(x: 0, y: 0, z: 0)
environmentNode.listenerAngularOrientation = AVAudio3DAngularOrientation(yaw: 0, pitch: 0, roll: 0)
environmentNode.distanceAttenuationParameters.referenceDistance = 1.0 environmentNode.distanceAttenuationParameters.maximumDistance = 100.0
environmentNode.distanceAttenuationParameters.rolloffFactor = 2.0
// example.mp3 is mono sound
guard let audioURL = Bundle.main.url(forResource: "example", withExtension: "mp3") else {
print("Audio file not found")
return
}
do {
audioFile = try AVAudioFile(forReading: audioURL)
} catch {
print("Failed to load audio file: \(error)")
}
}
...
//Playing sound
func playSpatialAudio(pan: Float ) {
guard let audioFile = audioFile else { return }
// left side
playerNode.position = AVAudio3DPoint(x: pan, y: 0, z: 0)
playerNode.scheduleFile(audioFile, at: nil, completionHandler: nil)
do {
try audioEngine.start()
playerNode.play()
} catch {
print("Failed to start audio engine: \(error)")
}
...
}
Second more complex approach using PHASE did better. I’ve made an exemplary app that allows players to move audio player in 3D space. I have added reverb, and sliders changing audio position up to 10 meters each direction from listener but audio seems to only really change left to right (x axis) - again I think it might be trouble with the app not being recognized as spatial.
//Crucial class Variables:
class PHASEAudioController: ObservableObject{
private var soundSourcePosition: simd_float4x4 = matrix_identity_float4x4
private var audioAsset: PHASESoundAsset!
private let phaseEngine: PHASEEngine
private let params = PHASEMixerParameters()
private var soundSource: PHASESource
private var phaseListener: PHASEListener!
private var soundEventAsset: PHASESoundEventNodeAsset?
// Initialization of PHASE
init{
do {
let session = AVAudioSession.sharedInstance()
try session.setCategory(.playback, mode: .default, options: [])
try session.setActive(true)
} catch {
print("Failed to configure AVAudioSession: \(error.localizedDescription)")
}
// Init PHASE Engine
phaseEngine = PHASEEngine(updateMode: .automatic)
phaseEngine.defaultReverbPreset = .mediumHall
phaseEngine.outputSpatializationMode = .automatic //nothing helps
// Set listener position to (0,0,0) in World space
let origin: simd_float4x4 = matrix_identity_float4x4
phaseListener = PHASEListener(engine: phaseEngine)
phaseListener.transform = origin
phaseListener.automaticHeadTrackingFlags = .orientation
try! self.phaseEngine.rootObject.addChild(self.phaseListener)
do{
try self.phaseEngine.start();
}
catch {
print("Could not start PHASE engine")
}
audioAsset = loadAudioAsset()
// Create sound Source
// Sphere
soundSourcePosition.translate(z:3.0)
let sphere = MDLMesh.newEllipsoid(withRadii: vector_float3(0.1,0.1,0.1), radialSegments: 14, verticalSegments: 14, geometryType: MDLGeometryType.triangles, inwardNormals: false, hemisphere: false, allocator: nil)
let shape = PHASEShape(engine: phaseEngine, mesh: sphere)
soundSource = PHASESource(engine: phaseEngine, shapes: [shape])
soundSource.transform = soundSourcePosition
print(soundSourcePosition)
do {
try phaseEngine.rootObject.addChild(soundSource)
}
catch {
print ("Failed to add a child object to the scene.")
}
let simpleModel = PHASEGeometricSpreadingDistanceModelParameters()
simpleModel.rolloffFactor = rolloffFactor
soundPipeline.distanceModelParameters = simpleModel
let samplerNode = PHASESamplerNodeDefinition(
soundAssetIdentifier: audioAsset.identifier,
mixerDefinition: soundPipeline,
identifier: audioAsset.identifier + "_SamplerNode")
samplerNode.playbackMode = .looping
do {soundEventAsset = try
phaseEngine.assetRegistry.registerSoundEventAsset(
rootNode: samplerNode,
identifier: audioAsset.identifier + "_SoundEventAsset")
} catch {
print("Failed to register a sound event asset.")
soundEventAsset = nil
}
}
//Playing sound
func playSound(){
// Fire new sound event with currently set properties
guard let soundEventAsset else { return }
params.addSpatialMixerParameters(
identifier: soundPipeline.identifier,
source: soundSource,
listener: phaseListener)
let soundEvent = try! PHASESoundEvent(engine: phaseEngine,
assetIdentifier: soundEventAsset.identifier,
mixerParameters: params)
soundEvent.start(completion: nil)
}
...
}
Also worth mentioning might be that I only own personal team account
I'm using AVFoundation to make a multi-track editor app, which can insert multiple track and clip, including scale some clip to change the speed of the clip, (also I'm not sure whether AVFoundation the best choice for me) but after making the scale with scaleTimeRange API, there is some short noise sound in play back. Also, sometimes it's fine when play AVMutableCompostion using AVPlayer with AVPlayerItem, but after exporting with AVAssetReader, will catch some short noise sounds in result file.... Not sure why.
Here is the example project, which can build and run directly. https://github.com/luckysmg/daily_images/raw/refs/heads/main/TestDemo.zip
Hi there!
We have a suite of AudioUnit v2 plugins that have been shipped for some time as aufx plugins, and we are looking into MIDI-related platform upgrades, so we need a way to update these plugins to request MIDI from Logic (and other AU hosts) but avoid changing our AU type and subtype so we don't break existing sessions. Any ideas on how we can do this?
When multiple identical songs are added to a playlist, Playlist.Entry.id uses a suffix-based identifier (e.g. songID_0, songID_1, etc.). Removing one entry causes others to shift, changing their .id values. This leads to diffing errors and collection view crashes in SwiftUI or UIKit when entries are updated.
Steps to Reproduce:
Add the same song to a playlist multiple times.
Observe .id.rawValue of entries (e.g. i.SONGID_0, i.SONGID_1).
Remove one entry.
Fetch playlist again — note the other IDs have shifted.
FB18879062
I'm streaming mp3 audio data using URLSession/AudioFileStream/AVAudioConverter and getting occasional silent buffers and glitches (little bleeps and whoops as opposed to clicks). The issues are present in an offline test, so this isn't an issue of underruns.
Doing some buffering on the input coming from the URLSession (URLSessionDataTask) reduces the glitches/silent buffers to rather infrequent, but they do still happen occasionally.
var bufferedData = Data()
func parseBytes(data: Data) {
bufferedData.append(data)
// XXX: this buffering reduces glitching
// to rather infrequent. But why?
if bufferedData.count > 32768 {
bufferedData.withUnsafeBytes { (bytes: UnsafeRawBufferPointer) in
guard let baseAddress = bytes.baseAddress else { return }
let result = AudioFileStreamParseBytes(audioStream!,
UInt32(bufferedData.count),
baseAddress,
[])
if result != noErr {
print("❌ error parsing stream: \(result)")
}
}
bufferedData = Data()
}
}
No errors are returned by AudioFileStream or AVAudioConverter.
func handlePackets(data: Data,
packetDescriptions: [AudioStreamPacketDescription]) {
guard let audioConverter else {
return
}
var maxPacketSize: UInt32 = 0
for packetDescription in packetDescriptions {
maxPacketSize = max(maxPacketSize, packetDescription.mDataByteSize)
if packetDescription.mDataByteSize == 0 {
print("EMPTY PACKET")
}
if Int(packetDescription.mStartOffset) + Int(packetDescription.mDataByteSize) > data.count {
print("❌ Invalid packet: offset \(packetDescription.mStartOffset) + size \(packetDescription.mDataByteSize) > data.count \(data.count)")
}
}
let bufferIn = AVAudioCompressedBuffer(format: inFormat!, packetCapacity: AVAudioPacketCount(packetDescriptions.count), maximumPacketSize: Int(maxPacketSize))
bufferIn.byteLength = UInt32(data.count)
for i in 0 ..< Int(packetDescriptions.count) {
bufferIn.packetDescriptions![i] = packetDescriptions[i]
}
bufferIn.packetCount = AVAudioPacketCount(packetDescriptions.count)
_ = data.withUnsafeBytes { ptr in
memcpy(bufferIn.data, ptr.baseAddress, data.count)
}
if verbose {
print("handlePackets: \(data.count) bytes")
}
// Setup input provider closure
var inputProvided = false
let inputBlock: AVAudioConverterInputBlock = { packetCount, statusPtr in
if !inputProvided {
inputProvided = true
statusPtr.pointee = .haveData
return bufferIn
} else {
statusPtr.pointee = .noDataNow
return nil
}
}
// Loop until converter runs dry or is done
while true {
let bufferOut = AVAudioPCMBuffer(pcmFormat: outFormat, frameCapacity: 4096)!
bufferOut.frameLength = 0
var error: NSError?
let status = audioConverter.convert(to: bufferOut, error: &error, withInputFrom: inputBlock)
switch status {
case .haveData:
if verbose {
print("✅ convert returned haveData: \(bufferOut.frameLength) frames")
}
if bufferOut.frameLength > 0 {
if bufferOut.isSilent {
print("(haveData) SILENT BUFFER at frame \(totalFrames), pending: \(pendingFrames), inputPackets=\(bufferIn.packetCount), outputFrames=\(bufferOut.frameLength)")
}
outBuffers.append(bufferOut)
totalFrames += Int(bufferOut.frameLength)
}
case .inputRanDry:
if verbose {
print("🔁 convert returned inputRanDry: \(bufferOut.frameLength) frames")
}
if bufferOut.frameLength > 0 {
if bufferOut.isSilent {
print("(inputRanDry) SILENT BUFFER at frame \(totalFrames), pending: \(pendingFrames), inputPackets=\(bufferIn.packetCount), outputFrames=\(bufferOut.frameLength)")
}
outBuffers.append(bufferOut)
totalFrames += Int(bufferOut.frameLength)
}
return // wait for next handlePackets
case .endOfStream:
if verbose {
print("✅ convert returned endOfStream")
}
return
case .error:
if verbose {
print("❌ convert returned error")
}
if let error = error {
print("error converting: \(error.localizedDescription)")
}
return
@unknown default:
fatalError()
}
}
}
I want the audio session to always use the built-in microphone. However, when using the setPreferredInput() method like in this example
private func enableBuiltInMic() {
// Get the shared audio session.
let session = AVAudioSession.sharedInstance()
// Find the built-in microphone input.
guard let availableInputs = session.availableInputs,
let builtInMicInput = availableInputs.first(where: { $0.portType == .builtInMic }) else {
print("The device must have a built-in microphone.")
return
}
// Make the built-in microphone input the preferred input.
do {
try session.setPreferredInput(builtInMicInput)
} catch {
print("Unable to set the built-in mic as the preferred input.")
}
}
and calling that function once in the initializer,
the audio session still switches to the external microphone once one is plugged in.
The session's preferredInput is nil again at that point, even if the built-in microphone is still listed in availableInputs.
So,
why is the preferredInput suddenly reset?
when would be the appropriate time to set the preferredInput again?
Observing the session’s availableInputs did not work and setting the preferredInput again in the routeChangeNotification handler seems a bad choice as it’s already a bit too late then.
Hi all, I have spent a lot of time reading the tech note and watching the WDDC video that introduce the PTTFramework on iOS. I currently have a custom setup where I am using AVAudioEngine to schedule and play buffers that are being streamed through a call.
I am looking to use the PTTFramework to allow a user to trigger this push to talk behavior from the lock screen and the various places with the system UI it provides.
However I am unsure what the correct behavior is regarding the handling of the audio session. Right now I am using .playback when there is no active voice transmission so that devices such as AirPods can be in AD2P mode where applicable, and then transitioning to .playbackAndRecord category only when the mic input should become active. Following this change in my AVAudioEngine manager I am then manually activating and deactivating the audio session manually when the engine is either playing/recording or idle.
In the documentation it states that you should not attempt to activate or deactivate your audio session directly, but allow the framework to handle it.
Does that mean that I need to either call the request to transmit delegate function or set an active participant on the channel manager first, and then wait for the didBecomeActive delegate method to trigger before I actually attempt to play or record any audio? (I am using the fullDuplex mode currently.) I noticed that that delegate method will only trigger if the audio session wasn't active before doing one of the above (setting active participant, requesting transmit).
Lastly, when using the PTTFramework it also mentions that we get support for PTT devices and I notice on the didBeginTransmittingFrom property we have a handsfreeButton case. Is there any documentation or resources for what is actually supported out of the box for this? I am currently working on handling a lot of the push to talk through bluetooth LE, and wanted to make sure there wasn't overlap with what the system provides.
Thank you!
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 bought two "Apple USB-C to Headphone Jack Adapters". Upon closer inspection, they seems to be of different generations:
The one with product ID 0x110a on top is working fine. The one with product ID 0x110b has two issues:
There is a short but loud click noise on the headphone when I connect it to the iPad.
When I play audio using AVAudioPlayer the first half of a second or so is cut off.
Here's how I'm playing the audio:
audioPlayer = try AVAudioPlayer(contentsOf: url)
audioPlayer?.delegate = self
audioPlayer?.prepareToPlay()
audioPlayer?.play()
Is this a known issue? Am I doing something wrong?