Hi everyone,
I'm running into an issue with AVAudioRecorder when handling interruptions such as phone calls or alarms.
Problem:
When the app is recording audio and an interruption occurs:
I handle the interruption with audioRecorder?.pause() inside AVAudioSession.interruptionNotification (on .began).
On .ended, I check for .shouldResume and call audioRecorder?.record() again.
The recorder resumes successfully, but only the audio recorded after the interruption is saved. The audio recorded before the interruption is lost, even though I'm using the same file URL and not recreating the recorder.
Repro:
Start a recording with AVAudioRecorder
Simulate a system interruption (e.g., incoming call)
Resume recording after the interruption
Stop and inspect the output audio file
Expected: Full audio (before and after interruption) should be saved.
Actual: Only the audio after interruption is saved; the earlier part is missing
Notes:
According to the documentation, calling .record() after .pause() should resume recording into the same file.
I confirmed that the file URL does not change, and I do not recreate the recorder instance.
No error is thrown by the system during this process.
This behavior happens consistently when the app is interrupted and resumed.
Question:
Is this a known issue? Is there a recommended workaround for preserving the full recording when interruptions happen?
Thanks in advance!
Audio
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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
I'm developing a TTS Audio Unit Extension that needs to write trace/log files to a shared App Group container. While the main app can successfully create and write files to the container, the extension gets sandbox denied errors despite having proper App Group entitlements configured.
Setup:
Main App (Flutter) and TTS Audio Unit Extension share the same App Group
App Group is properly configured in developer portal and entitlements
Main app successfully creates and uses files in the container
Container structure shows existing directories (config/, dictionary/) with populated files
Both targets have App Group capability enabled and entitlements set
Current behavior:
Extension can access/read the App Group container
Extension can see existing directories and files
All write attempts are blocked with "sandbox deny(1) file-write-create" errors
Code example:
const char* createSharedGroupPathWithComponent(const char* groupId, const char* component) {
NSString* groupIdStr = [NSString stringWithUTF8String:groupId];
NSString* componentStr = [NSString stringWithUTF8String:component];
NSURL* url = [[NSFileManager defaultManager]
containerURLForSecurityApplicationGroupIdentifier:groupIdStr];
NSURL* fullPath = [url URLByAppendingPathComponent:componentStr];
NSError *error = nil;
if (![[NSFileManager defaultManager] createDirectoryAtPath:fullPath.path
withIntermediateDirectories:YES
attributes:nil
error:&error]) {
NSLog(@"Unable to create directory %@", error.localizedDescription);
}
return [[fullPath path] UTF8String];
}
Error output:
Sandbox: simaromur-extension(996) deny(1) file-write-create /private/var/mobile/Containers/Shared/AppGroup/36CAFE9C-BD82-43DD-A962-2B4424E60043/trace
Key questions:
Are there additional entitlements required for TTS Audio Unit Extensions to write to App Group containers?
Is this a known limitation of TTS Audio Unit Extensions?
What is the recommended way to handle logging/tracing in TTS Audio Unit Extensions?
If writing to App Group containers is not supported, what alternatives are available?
Current entitlements:
<dict>
<key>com.apple.security.application-groups</key>
<array>
<string>group.com.<company>.<appname></string>
</array>
</dict>
Hello everyone,
I am working on an app that allows you to review your own music using Apple Music. Currently I am running into an issue with the skipping forwards and backwards outside of the app.
How it should work: When skipping forward or backwards on the lock or home screen of an iPhone, the next or previous song on an album should play and the information should change to reflect that in the app.
If you play a song in Apple Music, you can see a Now Playing view in the lock screen.
When you skip forward or backwards, it will do either action and it would reflect that when you see a little frequency icon on artwork image of a song.
What it's doing: When skipping forward or backwards on the lock or home screen of an iPhone, the next or previous song is reflected outside of the app, but not in the app.
When skipping a song outside of the app, it works correctly to head to the next song.
But when I return to the app, it is not reflected
NOTE: I am not using MusicKit variables such as Track, Album to display the songs. Since I want to grab the songs and review them I need a rating so I created my own that grabs the MusicItemID, name, artist(s), etc.
NOTE: I am using ApplicationMusicPlayer.shared
Is there a way to get the song to reflect in my app?
(If its easier, a simple example of it would be nice. No need to create an entire xprod file)
According to the header file the outputVolume properties supported range is 0.0-1.0:
/*! @property outputVolume
@abstract The mixer's output volume.
@discussion
This accesses the mixer's output volume (0.0-1.0, inclusive).
@property (nonatomic) float outputVolume;
However when setting the volume to 2.0 the audio does indeed play louder. Is the header file out of date and if so, what is the supported range for outputVolume?
Thanks
I'm working on adding CarPlay support to an audio app and am running into an issue. Occasionally, when a user opens the app from CarPlay while the main app scene is either not connected or is currently in the background, I will receive an error when attempting to activate the audio session. The code below mimics my setup:
do {
try AVAudioSession.sharedInstance().setCategory(.playback, mode: .spokenAudio)
try AVAudioSession.sharedInstance().setActive(true)
} catch {
print(error) // NSOSStatusErrorDomain - 560557684: Session activation failed
}
That error code maps to AVAudioSession.ErrorCode.cannotInterruptOthers.
Once in this state, all subsequent attempts to play different pieces of content will fail. However, things will start working normally if the user opens the app on their phone and tries again from CarPlay (while the app is in the foreground on their phone).
I'm not sure why it would behave this way and want to note that I do have the audio background mode capability enabled.
Has anyone else encountered this? Are there any workarounds or changes I could make to prevent this from happening?
I am developing an app that uses MusicKit to play music and then I need to have spoken words played to the user, while ducking the audio coming from MusicKit (application music player)
the built in Siri voices are not off sufficient quality so I am using an external service to create an mp3 file and then play this back using AVAudioSession
Sample code below
the problem I am having is that .duckOthers is not ducking the Application Music Player output
Is this a bug or am I doing this wrong?
// Configure audio session for system-wide ducking
try AVAudioSession.sharedInstance().setCategory(.playback, mode: .spokenAudio, options: [.duckOthers, .mixWithOthers])
try AVAudioSession.sharedInstance().setActive(true)
// Set the ducking level to maximum
try AVAudioSession.sharedInstance().setPreferredIOBufferDuration(0.005)
// Create and configure audio player
self.audioPlayer = try AVAudioPlayer(data: audioData)
self.audioPlayer?.delegate = self
self.audioPlayer?.volume = 1.0 // Ensure full volume for speech
self.audioPlayer?.prepareToPlay()
// Set the audio player's settings for maximum clarity
self.audioPlayer?.enableRate = false
self.audioPlayer?.pan = 0.0 // Center the audio
self.audioPlayer?.play()
Hi everyone,
I’m working on an iOS MusicKit app that overlays a metronome on top of Apple Music playback. To line the clicks up perfectly I’d like access to low-level audio analysis data—ideally a waveform / spectrogram or beat grid—while the track is playing.
I’ve noticed that several approved DJ apps (e.g. djay, Serato, rekordbox) can already:
• Display detailed scrolling waveforms of Apple Music songs
• Scratch, loop or time-stretch those tracks in real time
That implies they receive decoded PCM frames or at least high-resolution analysis data from Apple Music under a special entitlement.
My questions:
1. Does MusicKit (or any public framework) expose real-time audio buffers, FFT bins, or beat markers for streaming Apple Music content?
2. If not, is there an Apple program or entitlement that developers can apply for—similar to the “DJ with Apple Music” initiative—to gain that deeper access?
3. Where can I find official documentation or a point of contact for this kind of request?
I’ve searched the docs and forums but only see standard MusicKit playback APIs, which don’t appear to expose raw audio for DRM-protected songs. Any guidance, links or insider tips on the proper application process would be hugely appreciated!
Thanks in advance.
Hi everyone,
I’m working on an iOS MusicKit app that overlays a metronome on top of Apple Music playback. To line the clicks up perfectly I’d like access to low-level audio analysis data—ideally a waveform / spectrogram or beat grid—while the track is playing.
I’ve noticed that several approved DJ apps (e.g. djay, Serato, rekordbox) can already: • Display detailed scrolling waveforms of Apple Music songs • Scratch, loop or time-stretch those tracks in real time
That implies they receive decoded PCM frames or at least high-resolution analysis data from Apple Music under a special entitlement.
My questions: 1. Does MusicKit (or any public framework) expose real-time audio buffers, FFT bins, or beat markers for streaming Apple Music content? 2. If not, is there an Apple program or entitlement that developers can apply for—similar to the “DJ with Apple Music” initiative—to gain that deeper access? 3. Where can I find official documentation or a point of contact for this kind of request?
I’ve searched the docs and forums but only see standard MusicKit playback APIs, which don’t appear to expose raw audio for DRM-protected songs. Any guidance, links or insider tips on the proper application process would be hugely appreciated!
Thanks in advance.
Hi, In my project I am using AVFoundation for recording the audio. We are using AVAudioMixerNode class below method to record the audio packet.
**func installTap(
onBus bus: AVAudioNodeBus,
bufferSize: AVAudioFrameCount,
format: AVAudioFormat?,
block tapBlock: @escaping AVAudioNodeTapBlock
)
**
It works perfectly fine.
But in production env some small percentage of the user we are facing issue like after recording few packets it stops automatically without stopping the audio engine. Can anyone help here that why this happens? I have also observed for mediaServicesWereResetNotification and added log on receiving this notification but when this issue happens I don't see any occurence of this log. Also is there any callback when the engine stops?
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!
Does anyone know how to pronounce the sound of a specific instrument when you tap a button on the screen on your iPhone or iPad? Now, in the middle of creating a music learning app, I'm thinking of assigning monotones or chords to the button-like frames on the keyboard and fingerboard on the screen. Can it be achieved with SwiftUI chords alone? Once upon a time, MIDI level 1 I remember that there was a pronunciation function of the instrument, but I don't think about implementing the same function in the current OS. Please lend me your wisdom.
Topic:
Media Technologies
SubTopic:
Audio
Hello,
I'm trying to receive parquet files using the example that provided in documentation. I've done all required steps but receive constantly error 500 with "Upstream Service Error". By looking into the issues list, seems this error exists for months. Is it possible to get it working?
Hi everyone,
I’m working on an iOS MusicKit app that overlays a metronome on top of Apple Music playback, using ApplicationMusicPlayer. To line the clicks up perfectly I’d like access to low-level audio analysis data—ideally a waveform / spectrogram or beat grid—while the track is playing.
I’ve noticed that several approved DJ apps (e.g. djay, Serato, rekordbox) can already:
• Display detailed scrolling waveforms of Apple Music songs
• Scratch, loop or time-stretch those tracks in real time
That implies they receive decoded PCM frames or at least high-resolution analysis data from Apple Music under a special entitlement.
My questions:
Does MusicKit (or any public framework) expose real-time audio buffers, FFT bins, or beat markers for streaming Apple Music content?
If not, is there an Apple program or entitlement that developers can apply for—similar to the “DJ with Apple Music” initiative—to gain that deeper access?
Where can I find official documentation or a point of contact for this kind of request?
I’ve searched the docs and forums but only see standard MusicKit playback APIs, which don’t appear to expose raw audio for DRM-protected songs. Any guidance, links or insider tips on the proper application process would be hugely appreciated!
Thanks in advance.
Hello,
i can successfully match music using shazamkit on Apple using SwiftUI, a simple app that let user to load an audio file and exctracts the relative match, while i am unable to match music using shamzamkit on Android. I am trying to make the same simple app but i cannot match music as i get MATCH_ATTEMPT_FAILED every time i try to. I don't know what i am doing wrong but the shazam part in the kotlin Android code is in this method :
suspend fun processAudioFileInBackground(
filePath: String,
developerTokenProvider: DeveloperTokenProvider
) = withContext(Dispatchers.IO) {
val bufferSize = 1024 * 1024
val audioFile = FileInputStream(filePath)
val byteBuffer = ByteBuffer.allocate(bufferSize)
byteBuffer.order(ByteOrder.LITTLE_ENDIAN)
var bytesRead: Int
while (audioFile.read(byteBuffer.array()).also { bytesRead = it } != -1) {
val signatureGenerator = (ShazamKit.createSignatureGenerator(AudioSampleRateInHz.SAMPLE_RATE_44100) as ShazamKitResult.Success).data
signatureGenerator.append(byteBuffer.array(), bytesRead, System.currentTimeMillis())
val signature = signatureGenerator.generateSignature()
println("Signature: ${signature.durationInMs}")
val catalog = ShazamKit.createShazamCatalog(developerTokenProvider, Locale.ENGLISH)
val session = (ShazamKit.createSession(catalog) as ShazamKitResult.Success).data
val matchResult = session.match(signature)
println("MatchResult : $matchResult")
setMatchResult(matchResult)
byteBuffer.clear()
}
audioFile.close()
}
I noticed that changing Locale in catalog creation results in different result as i get NoMatch without exception. Can you please help me with this? Do i need to create a custom catalog?
Hi,
macOS (latest macOS, latest HW, but doesn't matter) seems to prevent CoreMIDI driver logging with standard logging procedures (syslog, unified logging).
The only chance to log something is writing to a file at one of the rare write-accessible locations for CoreMIDI.
How is this supposed to work? Any hint is highly appreciated. Thanks!
Hello!
I'm experiencing an issue with iOS's audio routing system when trying to use Bluetooth headphones for audio output while also recording environmental audio from the built-in microphone.
Desired behavior:
Play audio through Bluetooth headset (AirPods)
Record unprocessed environmental audio from the iPhone's built-in microphone
Actual behavior:
When explicitly selecting the built-in microphone, iOS reports it's using it (in currentRoute.inputs)
However, the actual audio data received is clearly still coming from the AirPods microphone
The audio is heavily processed with voice isolation/noise cancellation, removing environmental sounds
Environment Details
Device: iPhone 12 Pro Max
iOS Version: 18.4.1
Hardware: AirPods
Audio Framework: AVAudioEngine (also tried AudioQueue)
Code Attempted
I've tried multiple approaches to force the correct routing:
func configureAudioSession() {
let session = AVAudioSession.sharedInstance()
// Configure to allow Bluetooth output but use built-in mic
try? session.setCategory(.playAndRecord,
options: [.allowBluetoothA2DP, .defaultToSpeaker])
try? session.setActive(true)
// Explicitly select built-in microphone
if let inputs = session.availableInputs,
let builtInMic = inputs.first(where: { $0.portType == .builtInMic }) {
try? session.setPreferredInput(builtInMic)
print("Selected input: \(builtInMic.portName)")
}
// Log the current route
let route = session.currentRoute
print("Current input: \(route.inputs.first?.portName ?? "None")")
// Configure audio engine with native format
let inputNode = audioEngine.inputNode
let nativeFormat = inputNode.inputFormat(forBus: 0)
inputNode.installTap(onBus: 0, bufferSize: 1024, format: nativeFormat) { buffer, time in
// Process audio buffer
// Despite showing "Built-in Microphone" in route, audio appears to be
// coming from AirPods with voice isolation applied - welp!
}
try? audioEngine.start()
}
I've also tried various combinations of:
Different audio session modes (.default, .measurement, .voiceChat)
Different option combinations (with/without .allowBluetooth, .allowBluetoothA2DP)
Setting session.setPreferredInput() both before and after activation
Diagnostic Observations
When AirPods are connected:
AVAudioSession.currentRoute.inputs correctly shows "Built-in Microphone" after setPreferredInput()
The actual audio data received shows clear signs of AirPods' voice isolation processing
Background/environmental sounds are actively filtered out...
When recording a test audio played near the phone (not through the app), the recording is nearly silent. Only headset voice goes through.
Questions
Is there a workaround to force iOS to actually use the built-in microphone while maintaining Bluetooth output?
Are there any lower-level configurations that might resolve this issue?
Any insights, workarounds, or suggestions would be greatly appreciated. This is blocking a critical feature in my application that requires environmental audio recording while providing audio feedback through headphones 😅
Hi, I'm working on an AUv3 project.
The app itself displays my icon.
However the Auv3 extension does not display any icon in any host app (AUM, Drambo, etc.0).
I thought that the extension would inherit the host app icon but that it does not appear to be the case.
I tried to add the icon as a 1024x1024 file to the extension target and the update my extension plist file withe a CFBundleIconFile key but no luck either.
It must surely be really easy. What am I missing?
Thanks in advance for your help!
Topic:
Media Technologies
SubTopic:
Audio
I'm using a 4 channel USB Audio interface, with 4 microphones, and want to process them through 4 independent effect chains. However the output from AVAudioInputNode is a single 4 channel bus. How can I split this into 4 mono busses?
The following code splits the input into 4 copies, and routes them through the effects, but each bus contains all four channels. How can I remap the channels to remove the unwanted channels from the bus? I tried using channelMap on the mixer node but that had no effect.
I'm currently using this code primarily on iOS but it should be portable between iOS and MacOS. It would be possible to do this through a Matrix Mixer Node, but that seems completely overkill, for such a basic operation. I'm already using a Matrix Mixer to combine the inputs, and it's not well supported in AVAudioEngine.
AVAudioInputNode *inputNode=[engine inputNode];
[inputNode setVoiceProcessingEnabled:NO error:nil];
NSMutableArray *micDestinations=[NSMutableArray arrayWithCapacity:trackCount];
for(i=0;i<trackCount;i++)
{
fixMicFormat[i]=[AVAudioMixerNode new];
[engine attachNode:fixMicFormat[i]];
// And create reverb/compressor and eq the same way...
[engine connect:reverb[i] to:matrixMixerNode fromBus:0 toBus:i format:nil];
[engine connect:eq[i] to:reverb[i] fromBus:0 toBus:0 format:nil];
[engine connect:compressor[i] to:eq[i] fromBus:0 toBus:0 format:nil];
[engine connect:fixMicFormat[i] to:compressor[i] fromBus:0 toBus:0 format:nil];
[micDestinations addObject:[[AVAudioConnectionPoint alloc] initWithNode:fixMicFormat[i] bus:0] ];
}
AVAudioFormat *inputFormat = [inputNode outputFormatForBus: 1];
[engine connect:inputNode toConnectionPoints:micDestinations fromBus:1 format:inputFormat];
Hello,
Has anyone else experienced variations in the accuracy of the playbackTime value? After a few seconds of playback, the reported time adjusts by a fraction of a second, making it difficult to calculate the actual playbackTime of the audio.
This can be recreated by playing a song in MusicKit, recording the start time of the audio, playing for at least 10-20 seconds, and then comparing the playbackTime value to one calculated using the start time of the audio. In my experience this jump occurs after about 10 seconds of playback.
Any help would be appreciated.
Thanks!