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?
Audio
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I am developing an app with transcription and I am exploring ways to improve the transcription from the SpeechAnalyzer/Transcriber for technical terms. SFSpeech... recognition had the capability of being augmented by contextualStrings. Does something similar exist for SpeechAnalyzer/Transcriber? If so please point me towards the documentation and any sample code that may exist for this. If there are other options, please let me know.
Hi everyone,
I’m testing audio recording on an iPhone 15 Plus using AVFoundation.
Here’s a simplified version of my setup:
let settings: [String: Any] = [
AVFormatIDKey: Int(kAudioFormatLinearPCM),
AVSampleRateKey: 8000,
AVNumberOfChannelsKey: 1,
AVLinearPCMBitDepthKey: 16,
AVLinearPCMIsFloatKey: false
]
audioRecorder = try AVAudioRecorder(url: fileURL, settings: settings)
audioRecorder?.record()
When I check the recorded file’s sample rate, it logs:
Actual sample rate: 8000.0
However, when I inspect the hardware sample rate:
try session.setCategory(.playAndRecord, mode: .default)
try session.setActive(true)
print("Hardware sample rate:", session.sampleRate)
I consistently get:
`Hardware sample rate: 48000.0
My questions are:
Is the iPhone mic actually capturing at 8 kHz, or is it recording at 48 kHz and then downsampling to 8 kHz internally?
Is there any way to force the hardware to record natively at 8 kHz?
If not, what’s the recommended approach for telephony-quality audio (true 8 kHz) on iOS devices?
Thanks in advance for your guidance!
3
I am working on an application to get when input audio device is being used. Basically I want to know the application using the microphone (built-in or external)
This app runs on macOS. For Mac versions starting from Sonoma I can use this code:
int getAudioProcessPID(AudioObjectID process)
{
pid_t pid;
if (@available(macOS 14.0, *)) {
constexpr AudioObjectPropertyAddress prop {
kAudioProcessPropertyPID,
kAudioObjectPropertyScopeGlobal,
kAudioObjectPropertyElementMain
};
UInt32 dataSize = sizeof(pid);
OSStatus error = AudioObjectGetPropertyData(process, &prop, 0, nullptr, &dataSize, &pid);
if (error != noErr) {
return -1;
}
} else {
// Pre sonoma code goes here
}
return pid;
}
which works.
However, kAudioProcessPropertyPID was added in macOS SDK 14.0.
Does anyone know how to achieve the same functionality on previous versions?
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?
I'm experiencing a significant limitation with MusicKit's Dolby Atmos implementation on macOS and would appreciate clarification on whether this is intended behavior or if there are solutions available.
When streaming Dolby Atmos content through MusicKit's ApplicationMusicPlayer, the output is limited to 2-channel stereo, even when:
Audio MIDI Setup is configured for 7.1.4 (12-channel) output
The same tracks play in full multichannel through the native Apple Music app
Dolby Atmos is set to "Automatic" in Apple Music preferences
Please let me know if there is anyway to enable this. If not, is this documented anywhere? Thanks!
We are developing an apple music app on phone, the developed web works fine on chrome, but when i load it on webivew on my phone, i can't play the first song,
We doubt that the drm init, key exchange, session creation was on the music.play() function, while we trigger the play, the drm or session was not ok for play a real song, so it got an error
so we may wanna know:
what about the realative process of drm, key, session, etc in the play() function?
are there some state detect function to show weather the drm is ok?
Topic:
Media Technologies
SubTopic:
Audio
Tags:
Apple Music API
MusicKit
MusicKit JS
Apple Music Feed
I am trying to use AVAudioEngine for recording and playing for a voice chat kind of app, but when the speaker plays any audio while recording, the recording take the speaker audio as input. I want to filter that out. Are there any suggestions for the swift code
I have integrated the ShazamKit SDK into my iOS app and would like to implement the same functionality in my Android app.
My question is: Can I use the Android version of the ShazamKit SDK for commercial purposes?
After extensive research, I could not find any official information regarding the license of the Android version of the ShazamKit SDK.
Could you please provide a formal license statement?
Hello,
I’m new here. I'm developing an iOS app and I’d like to know whether it is possible to detect if a phone call is being recorded by another app running in the background.
I’ve already reviewed the documentation for CallKit and AVAudioSession, but I couldn’t find anything related. My expectation was that iOS might provide some callback or API to indicate if a call is being recorded (third-party apps), but so far I haven’t found a way.
My questions are:
Does iOS expose any API to detect if a call is being recorded?
If not, is there any indirect, Apple's policy compliant method (e.g., microphone usage events) that can be relied upon?
Or is this something that iOS explicitly prevents for privacyreasons?
Expecting solutions that align with Apple’s policies and would be accepted under the App Store Review Guidelines.
Thanks in advance for any guidance.
iPadOS 18.3 beta 3 (22D5055b) fixed the issue for me and my 7th generation iPad.
Topic:
Media Technologies
SubTopic:
Audio
After investing more than a week into getting a bunch of audio unit projects converted into app + appex + framework, they all are now correctly loaded in-process in the demo host app that is part of Xcode's template.
However, Logic Pro adamantly refuses to load them in-process.
Does Logic Pro simply not do that ever, or is there some hint or configuration my plugins need to provide to enable that? If it is unsupported, will it be supported in some future version of Logic?
The entire point of investing that week was performance, which is moot if it is impossible to test the impact of loading in-process in a real-world usage scenario.
Hi,
I'm working on a project that uses the AVSpeechSynthesizer and AVSpeechUtterance.
I discovered by chance that the AVSpeechSynthesizer automatically completes some words instead of just outputting what it's supposed to.
These are abbreviations for days of the week or months, but not all of them. I don't want either of them automatically completed, but only the specified text. The completion transcends languages.
I have written a short example program for demonstration purposes.
import SwiftUI
import AVFoundation
import Foundation
let synthesizer: AVSpeechSynthesizer = AVSpeechSynthesizer()
struct ContentView: View {
var body: some View {
VStack {
Button {
utter("mon")
} label: {
Text("mon")
}
.buttonStyle(.borderedProminent)
Button {
utter("tue")
} label: {
Text("tue")
}
.buttonStyle(.borderedProminent)
Button {
utter("thu")
} label: {
Text("thu")
}
.buttonStyle(.borderedProminent)
Button {
utter("feb")
} label: {
Text("feb")
}
.buttonStyle(.borderedProminent)
Button {
utter("feb", lang: "de-DE")
} label: {
Text("feb DE")
}
.buttonStyle(.borderedProminent)
Button {
utter("wed")
} label: {
Text("wed")
}
.buttonStyle(.borderedProminent)
}
.padding()
}
private func utter(_ text: String, lang: String = "en-US") {
let utterance = AVSpeechUtterance(string: text)
let voice = AVSpeechSynthesisVoice(language: lang)
utterance.voice = voice
synthesizer.speak(utterance)
}
}
#Preview {
ContentView()
}
Thank you
Christian
Hello,
I am wondering if it is possible to have audio from my AirPods be sent to my speech to text service and at the same time have the built in mic audio input be sent to recording a video?
I ask because I want my users to be able to say "CAPTURE" and I start recording a video (with audio from the built in mic) and then when the user says "STOP" I stop the recording.
I’ve been researching how to achieve a recording playback effect in iOS similar to the hands-free calling effect in the system’s phone app. How can this be implemented? I tried using the voice chat recording method, but found that the volume of the speaker output is too low. How should this issue be addressed? I couldn’t find a suitable API. Could you provide me with some documentation or sample code? Thank you.
Using the official SwiftTranscriptionSampleApp from WWDC 2025, speech transcription takes 14+ seconds from audio input to first result, making it unusable for real-time applications.
Environment
iOS: 26.0 Beta
Xcode: Beta 5
Device: iPhone 16 pro
Sample App: Official Apple SwiftTranscriptionSampleApp from WWDC 2025
Configuration Tested
Locale: en-US (properly allocated with AssetInventory.allocate(locale:)) and es-ES
Setup: All optimizations applied (preheating, high priority, model retention)
I started testing in my own app to replace SFSpeech API and include speech detection but after long fights with documentation (this part is quite terrible TBH) I tested the example (https://developer.apple.com/documentation/speech/bringing-advanced-speech-to-text-capabilities-to-your-app) and saw same results.
I added some logs to check the specific time:
🎙️ [20:30:41.532] ✅ Analyzer started successfully - ready to receive audio!
🎙️ [20:30:41.532] Listening for transcription results...
🎙️ [20:30:56.342] 🚀 FIRST TRANSCRIPTION RESULT after 14.810s: 'Hello' (isFinal: false)
Questions
Is this expected performance for iOS 26 Beta, because old SFSpeech is far faster?
Are there additional optimization steps for SpeechTranscriber?
Should we expect significant performance improvements in later betas?
I work on an iOS app that records video and audio. We've been getting reports for a while from users who are experiencing their video recordings being cut off. After investigating, I found that many users are receiving the AVAudioSessionMediaServicesWereResetNotification (.mediaServicesWereResetNotification) notification while recording. It's associated with the AVFoundationErrorDomain[-11819] error, which seems to indicate that the system audio daemon crashed. We have a handler registered to end the recording, show the user a prompt, and restart our AV sessions. However, from our logs this looks to be happening to hundreds of users every day and it's not an ideal user experience, so I would like to figure out why this is happening and if it's due to something that we're doing wrong.
The debug menu option to trigger the audio session reset is not of much use, because it can't be triggered unless you leave the app and go to system settings. So our app can't be recording video when the debug reset is triggered. So far I haven't found a way to reproduced the issue locally, but I can see that it's happening to users from logs.
I've found some posts online from developers experiencing similar issues, but none of them seem to directly address our issue. The system error doesn't include a userInfo dictionary, and as far as I can tell it's a system daemon crash so any logs would need to be captured from the OS.
Is there any way that I could get more information about what may be causing this error that I may have missed?
Topic:
Media Technologies
SubTopic:
Audio
New to iOS development and I've been trying to make heads or tails of the documentation. I know there is a difference between the data fields returned from songs from the user library and from the category, but whenever I search on the apple site I can't find a list of each. For example, Im trying to get the releaseDate of a song in my library, but it seems I'll have to cross-query either the catalog entry for the using song.catalogID or the song.irsc but when I try to use them I can't find a cross reference between the two. I'm totally turned around.
Also trying to determine if a song in my library has been favorited or not? isFavorited (or something similar) doesn't seem to be a thing. Using this code and trying to find a way to display a solid star if the song has been favorited or an empty one if it's not. Seems like a basic request but I can't find anything on how to do it. I've searched docs, googled, tried.
Does apple want us to query the user's Favorited Songs playlist or something? How do I know which playlist that is?
I know isFavorited isn't a thing, just using it here so you can see what my intension is:
HStack(spacing: 10) {
Image(systemName: song.isFavorited ? "star.fill" : "star")
.foregroundColor(song.isFavorited ? .yellow : .gray)
Image(systemName: "magnifyingglass")
}
Not able to record audio in AAC format with 96 kHz sample rate using AVAudioRecorder or Extended Audio File services with 96 kHz input audio from input device. The audio recording settings used are
let settings: [String: Any] = [
AVFormatIDKey: Int(kAudioFormatMPEG4AAC),
AVSampleRateKey: sampleRate
AVNumberOfChannelsKey: 1
AVEncoderAudioQualityKey: AVAudioQuality.high.rawValue
]
When tried using AVAudioEngine using AVAudioFile,
AVAudioFile(forWriting: fileURL, // file extension .m4a settings: fileSettings,
commonFormat: AVAudioCommonFormat.pcmFormatFloat32, interleaved: interleaved) else { return }
got error
CodecConverterFactory.cpp:977 unable to select compatible encoder sample rate
AudioConverter.cpp:1017 Failed to create a new in process converter -> from 1 ch, 96000 Hz, Float32 to 1 ch, 96000 Hz, aac (0x00000000) 0 bits/channel, 0 bytes/packet, 0 frames/packet, 0 bytes/frame, with status 1718449215
After updating to iOS 18.5, we’ve observed that outgoing audio from our app intermittently stops being transmitted during VoIP calls using AVAudioSession configured with .playAndRecord and .voiceChat. The session is set active without errors, and interruptions are handled correctly, yet audio capture suddenly ceases mid-call. This was not observed in earlier iOS versions (≤ 18.4). We’d like to confirm if there have been any recent changes in AVAudioSession, CallKit, or related media handling that could affect audio input behavior during long-running calls.
func configureForVoIPCall() throws {
try setCategory(
.playAndRecord, mode: .voiceChat,
options: [.allowBluetooth, .allowBluetoothA2DP, .defaultToSpeaker])
try setActive(true)
}