I'm encountering errors while using AVAudioEngine with voice processing enabled (setVoiceProcessingEnabled(true)) in scenarios where the input and output audio devices are not the same. This issue arises specifically with mismatched devices, preventing the application from functioning as expected. Works: Paired devices (e.g., MacBook Pro mic → MacBook Pro speakers) Fails: Mismatched devices (e.g., AirPods mic → MacBook Pro speakers) When using paired input and output devices: The setup works as expected. Example: MacBook Pro microphone → MacBook Pro speakers. When using mismatched devices: AVAudioEngine setup fails during aggregate device construction. Example: AirPods microphone → MacBook Pro speakers. Error logs indicate a channel count mismatch. Here are the partial logs. Due to the content limit, I cannot post the entire logs. AUVPAggregate.cpp:1000 client-side input and output formats do not match (err=-10875) AUVPAggregate.cpp:1036 err=-10875 AVAEInternal.h:109 [AVAudioEngineGraph.mm:1344:Initialize: (err = PerformCommand(*outputNode, kAUInitialize, NULL, 0)): error -10875 AggregateDevice.mm:329 Failed expectation of constructed aggregate (312): mInput.streamChannelCounts == inputStreamChannelCounts AggregateDevice.mm:331 Failed expectation of constructed aggregate (312): mInput.totalChannelCount == std::accumulate(inputStreamChannelCounts.begin(), inputStreamChannelCounts.end(), 0U) AggregateDevice.mm:182 error fetching default pair AggregateDevice.mm:329 Failed expectation of constructed aggregate (336): mInput.streamChannelCounts == inputStreamChannelCounts AggregateDevice.mm:331 Failed expectation of constructed aggregate (336): mInput.totalChannelCount == std::accumulate(inputStreamChannelCounts.begin(), inputStreamChannelCounts.end(), 0U) AUHAL.cpp:1782 ca_verify_noerr: [AudioDeviceSetProperty(mDeviceID, NULL, 0, isInput, kAudioDevicePropertyIOProcStreamUsage, theSize, theStreamUsage), 560227702] AudioHardware-mac-imp.cpp:3484 AudioDeviceSetProperty: no device with given ID AUHAL.cpp:1782 ca_verify_noerr: [AudioDeviceSetProperty(mDeviceID, NULL, 0, isInput, kAudioDevicePropertyIOProcStreamUsage, theSize, theStreamUsage), 560227702] AggregateDevice.mm:182 error fetching default pair AggregateDevice.mm:329 Failed expectation of constructed aggregate (348): mInput.streamChannelCounts == inputStreamChannelCounts AggregateDevice.mm:331 Failed expectation of constructed aggregate (348): mInput.totalChannelCount == std::accumulate(inputStreamChannelCounts.begin(), inputStreamChannelCounts.end(), 0U) Is it possible to use voice processing with different input/output devices? If yes, are there any specific configurations required to handle mismatched devices? How can we resolve channel count mismatch errors during aggregate device construction? Are there settings or API adjustments to enforce compatibility between input/output devices? Are there any workarounds or alternative approaches to achieve voice processing functionality with mismatched devices? For instance, can we force an intermediate channel configuration or downmix input/output formats?

I have a flutter iOS app that has some simple sound FX for button clicks, swipes, etc. In simulator and on real device the sound works fine, but when i upload the app to testflight (and App store) the sound FX don't play. When I upload the app to my phone via xcode I am using the release profile so I don't see what the difference could be. I have also gone through the archive that i uploaded and verified that the sound files are indeed there. I have other flutter apps that use sound but non since the iOS 26 update. I've tried 3 different flutter sound libraries and all face the same issue. Wondering if anyone else is seeing this issue or if I'm missing a simple permission or something that has changed recently? Thanks in advanced

Hello there, I'm trying to implement feature which uses AirPlay with Apple TV. I want to disconnect from the device programmatically when something happens. Under something I mean a situation when a user wants to stop broadcasting (for example close the PiP window on his phone). I use this snippet: try audioSession.setCategory(.playAndRecord, options: .defaultToSpeaker) try audioSession.setActive(true, options: .notifyOthersOnDeactivation) It works fine sometimes but not always (it works on iOS 18 but it doesn't on iOS 17 or ). So I thought it's a bug and create a ticker to feedback assistant (FB21220013). The support told me write a post on the forum.

Hi all, I've been working on some personal programming projects and have gotten into using the Apple Music API. I'm currently looking to get a list of recent songs using the /v1/me/recent/played/tracks endpoint and it's working well. However, I know there are some songs I've listened to multiple times in a row, and those are not showing up as unique tracks when querying this endpoint. I'm only seeing a list of the different songs I've listened to lately, not a true list of the most recent plays on my account. Is this intended behavior or am I going about something incorrectly here? My query is using that endpoint & specifying the types to be only [songs]. Thanks in advance for any ideas or insight.

Hi team, In the Apple Music Feed datasets, we've noticed some unexpected values in the song and album tables. The primaryartists column from either song or album may contain a "non-default" artist name such as the katakana name shown in the example below: select id, name, namedefault, primaryartists from amf_song where id = '1698723329' id | name | namedefault | primaryartists ---------------------------------------- 1698723329 | {default=California} | California | [{id=1264818718, name=チャペル・ローン}] select * from amf_artist where id = '1264818718' id | name | namedefault | namepronunciation | ---------------------------------------------- 1264818718 | {default=Chappell Roan, ja=チャペル・ローン} | Chappell Roan | {ja=チャペルローン} | Shouldn't the primaryartists column be showing the namedefault instead of the Japanese language version? When can we expect this bug to resolved? Thanks,

Hello, We are trying to use the new Background Upload Extension to improve uploads of assets (Photos, Live Photos, Videos) in the background in our application. 1 - We implemented the code to upload still images. We would like to do the same for Live Photos but we are not sure how to proceed since a Live Photo is composed of 2 resources that we would like to upload in the same job so that we keep the association between the 2 resources. Steps: A Live Photo is captured on the device. Our application is notified for new content in the Photo Library and the asset is queued for upload by our application. The system calls the background upload extension and the Live Photo is prepared for upload but we can schedule a job only for one resource (still photo or paired video) so we can not upload both resources in a single job. 2 - Is there a way to synchronise the application and the extension so that the application would not process the same data or execute the same requests than the extension. For example: our application is working with tokens and we would like to prevent those tokens to be consumed by the application and the extension at the same time. 3 - is there a command in xcode or terminal to start or stop the extension, something similar to what exists for processing tasks (https://developer.apple.com/documentation/backgroundtasks/starting-and-terminating-tasks-during-development).

I am new to Swift and iOS development, and I have a question about video capture performance. Is it possible to capture video at a resolution of 4032×3024 while simultaneously running a vision/ML model on the video stream (e.g., using Vision or CoreML)? I want to know: whether iOS devices support capturing video at that resolution, whether the frame rate drops significantly at that scale, and whether it is practical to run a Vision/ML model in real-time while recording at such a high resolution. If anyone has experience with high-resolution AVCaptureSession setups or combining them with real-time ML processing, I would really appreciate guidance or sample code.

PHPhotoLibrary.authorizationStatus(for: .readWrite) == .authorized Iinfo.plist Privacy - Photo Library Usage Description set I check authorization before attempting to get the photoPickerItem.itemIdentifier, but every time the return value from itemIdentifier is nil. Seems I missing some permissions, but unsure why the system is still keeping _shouldExposeItemIdentifier set to false.

Hey, There seems to be an inconsistency when capturing a photo using QualityPrioritization.Quality on the iPhone 17 Pro Main wide Lens. If you zoom above "2x" the output image always has "-2.0ev" bias in the meta data and looks underexposued. This does not happen at zoom levels above 2, or if you set the QualityPrioritization to .Balanced. See below: with .Quality with .Balanced This does not happen on the other lenses. I'm using a simple set up and it is consistent across JPEG and ProRAW capture. I have a demo project if that is useful. Thanks, Alex

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 wrote a Swift macOS app to control a PCI audio device. The code switches between the default output and input channels. As soon as I launch the Audio-Midi Setup utility, channel switching stops working. The driver properties allow switching, but the system doesn't respond. I have to delete the contents of /Library/Preferences/Audio and reset Core Audio. What am I missing? func setDefaultChannelsOutput() { guard let deviceID = getDeviceIDByName(deviceName: "PCI-424") else { return } let selectedIndex = DefaultChannelsOutput.indexOfSelectedItem if selectedIndex < 0 || selectedIndex >= 24 { return } let channel1 = UInt32(selectedIndex * 2 + 1) let channel2 = UInt32(selectedIndex * 2 + 2) var channels: [UInt32] = [channel1, channel2] var propertyAddress = AudioObjectPropertyAddress( mSelector: kAudioDevicePropertyPreferredChannelsForStereo, mScope: kAudioDevicePropertyScopeOutput, mElement: kAudioObjectPropertyElementWildcard ) let dataSize = UInt32(MemoryLayout<UInt32>.size * channels.count) let status = AudioObjectSetPropertyData(deviceID, &propertyAddress, 0, nil, dataSize, &channels) if status != noErr { print("Error setting default output channels: \(status)") } }

We’re developing an AVFoundation-based video recording app (4K @ 60 fps required for biomechanical analysis). On most devices this works perfectly (iPhone 12/14/15/16 non-Pro models), but on several iPhone Pro models (12 Pro, 13 Pro, 14 Pro, 15 Pro/Pro Max), we consistently get 4K 30 fps recordings—even when the device should support 4K 60 fps on the wide-angle camera. What we observe We configure the session for .hd4K3840x2160. We iterate through AVCaptureDevice.formats and select formats that: have 3840×2160 resolution support ≥60 fps (videoSupportedFrameRateRanges) On some Pro devices, this format search returns no results, even though: The Camera app records 4K60 fine. External references list the wide camera as 4K60 capable. The fallback becomes the device's default 4K30 format, so final files are 3840×2160 @ 30 fps. This happens immediately on app launch (not after heating), so not thermal-related. What we’ve tried Force selecting .builtInWideAngleCamera instead of dual/triple cameras. Disabling HDR (videoHDREnabled = false). Disabling low-light boost. Allowing 59.94 fps formats (in case exact 60.0 isn’t exposed). Logging all videoSupportedFrameRateRanges per format. What we’re seeing in logs On affected Pro devices, the capture device reports only 4K formats with maxFrameRate ≈ 30 fps, despite the hardware being able to do 4K60. Main question Has anyone encountered cases where 4K60 formats are available in the Camera app but not exposed through AVFoundation, especially on Pro models or multi-camera devices? Could HEVC/HDR capability or multi-camera constraints be preventing certain formats from appearing? Are there known conditions where 4K60 formats are hidden unless specific device configuration is applied? Any guidance on reliably locking 4K60 on iPhone Pro models via AVFoundation would be hugely appreciated.

Our license service is based on version 4.5.4 and we make use of sample .c/.h files for building license service. We are told that version 4.5.4 is going to be deprecated in 2026 and we should migrate to latest SDK version 26. When explored the SDK, we noticed that only python and Swift based SDk is provided. Does Apple also provide C/C++ based SDK as it is going to easier for us to integrate. If yes, please share the SDK package and sample license service solution.

We are experiencing an issue related to DepthData from the TrueDepth camera on a specific device. On December 1, we tested with the complainant’s device iPhone 14 / iOS 26.0.1, and observed that the depth image is received with empty values. However, the same implementation works normally on iPhone 17 Pro Max (iOS 26.1) and iPhone 13 Pro Max (iOS 26.0.1), where depth data is delivered correctly. In the problematic case: TrueDepth camera is active Face ID works normally The app receives a DepthData object, but all values are empty (0), not nil Because the DepthData object is not nil, this makes it difficult to detect the issue through software fallback handling. We developed the feature with reference to the following Apple sample: https://developer.apple.com/documentation/AVFoundation/streaming-depth-data-from-the-truedepth-camera We would like to ask: Are there known cases where Face ID functions normally but DepthData from the TrueDepth camera is returned as empty values? If so, is there a recommended approach for identifying or handling this situation? Any guidance from Apple engineers or the community would be greatly appreciated. Thank you.

Hello, As far as I know and in all of my testing there is no way for a user or a developer to change the frame rate of the video output on iPadOS. If you connect an iPad via a USB Hub or a USB to HDMI Adaptor and then connect it to an external monitor it will output at 59.94fps. I have a video app where a user monitors live video at 25fps and 30fps, they often output to an external display and there are times when the external display will stutter due to the mismatch in frame rate, ie. using 25fps and outputting at 59.94fps. I thought it was impossible to change the video output frame rate, then in V3.1 of the Blackmagic Camera App I saw an interesting change in their release notes: ‘Support for HDMI Monitoring at Sensor Rate and Resolution’ This means there is some way to modify it, not sure if this is done via a Private API that Apple has allowed Blackmagic to use. If so, how can we access this or is there a way to enable this that is undocumented? Thanks!

For iOS17 we've had no problem playing Apple Fairplay encrypted content with keys delivered from our key server running on FairPlay Streaming Server SDK 5.1 and subsequently FairPlay Streaming Server SDK 26. It's built and deployed using Xcode Version 26.1.1 (17B100) with no changes to the code and - as expected - the content continued to be successfully decrypted and played (so far so good). However, as soon as a device was updated to iOS26, that device would no longer play the encrypted content. Devices remaining on iOS17 continue to work normally and the debugging logs are a sanity-check that proves that. Is anyone else experiencing this issue? Here's the code (you should be able to drop it into a fresh iOS Xcode project and provide a server url, content url and certificate).

Hi folks - I'm having trouble finding specific documentation about Audio Unit MIDI plugins - as in MIDI -only. Any suggestions welcome as searches aren't returning much. (too niche? user error?)

Hello, I requested Fairplay credentials a week ago. Where can I check the status of my request? Thank you very much. The team ID is: 6WZ8SVRYV9

I'm using this library: https://github.com/Yummypets/YPImagePicker to capture photos. I've modified it slightly, and I'm using an older version. When testing on my iPhone 16e, ios 26, whenever I take a photo, I get the following two error messages: <<<< FigXPCUtilities >>>> signalled err=-17281 at <>:302 <<<< FigCaptureSourceRemote >>>> Fig assert: "err == 0 " at bail (FigCaptureSourceRemote.m:569) - (err=-17281) These error messages appear, but as far as I can tell, the photo comes through OK, and I can save the data no problem. I've even removed all my handling code to see if it was something I was doing. I don't really want to ship with these errors showing, but I also have no idea what can be causing this error to appear. chatgpt was not helpful diagnosing this. Does anyone know what can cause this error Is there a way I can see the source code to figure out if there's something I'm doing wrong here? It really seems like this is an internal apple error, or else I would have expected more details on the error relating to the code I've written. Any clues would be appreciated!

Avplayer encapsulates a player. After connecting to an Apple Bluetooth headset, it immediately reports an error. Non-Apple Bluetooth headsets can be played, but currently the issue is that the player works normally in one app but not in another. We are an educational app.