When using AVSampleBufferDisplayLayer to play uncompressed H.264 and H.265 video with B-frames more than 7, frame drops occur. The more B-frames there are, the more noticeable the frame drops become, for example 15 bframes. Use FFmpeg to transcode a video file with visible timestamps and frame numbers (x264 or x265 ): ffmpeg -i test.mp4 -vf "drawtext=fontsize=45:text=%{pts} %{n}:y=400" -c:v libx264 -x264-params "bframes=15:b-adapt=0" -crf 30 -y x264_bf15.mp4 ffmpeg -i test.mp4 -vf "drawtext=fontsize=45:text=%{pts} %{n}:y=400" -c:v libx265 -x265-params "bframes=15:b-adapt=0" -crf 30 -y x265_bf15.mp4 Use the demo player from this repository to reproduce the issue: https://github.com/msfrms/CustomPlayer frame drops can be observed. And following log can be found in devices console. mediaserverd <<<< IQ-CA >>>> piqca_gmstats_dump: FIQCA(0x1266f4000) recent frames: enqueued: 184, displayed: 138, dropped: 42, flushed: 0, evicted: 3, >16ms late: 2 PS. I was using iphone11 iOS14.6, to replay this issue. May I ask why frame drops occur in this case? Is there any configuration or API usage change that could help fix the frame drop issue? Many thanks!

Recurring crash on install of any app with the new sourceVideoTrackProvider.next() dyld[41966]: Symbol not found: _$sSo19AVAssetReaderOutputC12AVFoundationE8ProviderC4nextxSgyYaKFTjTu Referenced from: <79AA2BE0-A6B4-32F5-A804-E84BBE5D1AEA> /Users/<username>/Library/Developer/Xcode/DerivedData/TrackProviderCrash-bbbhjptcxnmfdcackxtpucnunxyc/Build/Products/Debug-maccatalyst/TrackProviderCrash.app/Contents/MacOS/TrackProviderCrash.debug.dylib Expected in: <1B847AF9-7973-3B28-95C2-09E73F6DD50B> /usr/lib/swift/libswiftAVFoundation.dylib Can be reproduced with the current Xcode Beta 4 by running on to MacCatalyst and macOS https://developer.apple.com/documentation/AVFoundation/converting-projected-video-to-apple-projected-media-profile Crash goes away of you comment out lines 154-158 and 164-170 which are while let sampleBuffer = try await sourceVideoTrackProvider.next(){/*other code*/} Can also be reproduced if you add the code below to a MacCatalyst project import AVKit let asset: AVURLAsset = .init(url: Bundle.main.url(forResource: "SomeVideo.mp4", withExtension: nil)!) let videoReader = try! AVAssetReader(asset: asset) let videoTracks = try! await asset.loadTracks(withMediaCharacteristic: .visual) // Get the side-by-side video track. let videoTrack = videoTracks.first! let videoInputTrack = AVAssetReaderTrackOutput(track: videoTrack, outputSettings: nil) let sourceVideoTrackProvider: AVAssetReaderOutput.Provider<CMReadySampleBuffer<CMSampleBuffer.DynamicContent>> = videoReader.outputProvider(for: videoInputTrack) //Comment out this while let sb = try! await sourceVideoTrackProvider.next() { }

i'm trying to work on a simple screen recording app on macOS that always records the last 'x' seconds of your screen and saves it whenever you want, as a way to get comfortable with swift programming and apple APIs. i was able to get it running for the past '30 seconds' and record and store it. however i realised that there was a core issue with my solution: i was defining the SCStreamConfiguration.queueDepth = 900 (to account for 30fps for 30 seconds) which goes completely against apple's instructions: https://developer.apple.com/documentation/screencapturekit/scstreamconfiguration/queuedepth?language=objc now when i changed queueDepth back to 8, i am only able to record 8 frames and it saves only those first 8 frames. i am unsure what the flow of the apis should be while dealing with screenCaptureKit. for context, here's my recording manager code that handles this logic (queueDepth = 900) import Foundation import ScreenCaptureKit import AVFoundation class RecordingManager: NSObject, ObservableObject, SCStreamDelegate { static let shared = RecordingManager() @Published var isRecording = false private var isStreamActive = false // Custom state flag private var stream: SCStream? private var streamOutputQueue = DispatchQueue(label: "com.clipback.StreamOutput", qos: .userInteractive) private var screenStreamOutput: ScreenStreamOutput? // Strong reference to output private var lastDisplayID: CGDirectDisplayID? private let displayCheckQueue = DispatchQueue(label: "com.clipback.DisplayCheck", qos: .background) // In-memory rolling buffer for last 30 seconds private var rollingFrameBuffer: [(CMSampleBuffer, CMTime)] = [] private let rollingFrameBufferQueue = DispatchQueue(label: "com.clipback.RollingBuffer", qos: .userInteractive) private let rollingBufferDuration: TimeInterval = 30.0 // seconds // Track frame statistics private var frameCount: Int = 0 private var lastReportTime: Date = Date() // Monitor for display availability private var displayCheckTimer: Timer? private var isWaitingForDisplay = false func startRecording() { print("[DEBUG] startRecording called.") guard !isRecording && !isWaitingForDisplay else { print("[DEBUG] Already recording or waiting, ignoring startRecording call") return } isWaitingForDisplay = true isStreamActive = true // Set active state checkForDisplay() } private func setupAndStartRecording(for display: SCDisplay, excluding appToExclude: SCRunningApplication?) { print("[DEBUG] setupAndStartRecording called for display: \(display.displayID)") let excludedApps = [appToExclude].compactMap { $0 } let filter = SCContentFilter(display: display, excludingApplications: excludedApps, exceptingWindows: []) let config = SCStreamConfiguration() config.width = display.width config.height = display.height config.minimumFrameInterval = CMTime(value: 1, timescale: 30) // 30 FPS config.queueDepth = 900 config.showsCursor = true print("[DEBUG] SCStreamConfiguration created: width=\(config.width), height=\(config.height), FPS=\(config.minimumFrameInterval.timescale)") stream = SCStream(filter: filter, configuration: config, delegate: self) print("[DEBUG] SCStream initialized.") self.screenStreamOutput = ScreenStreamOutput { [weak self] sampleBuffer, outputType in guard let self = self else { return } guard outputType == .screen else { return } guard sampleBuffer.isValid else { return } guard let attachments = CMSampleBufferGetSampleAttachmentsArray(sampleBuffer, createIfNecessary: false) as? [[SCStreamFrameInfo: Any]], let statusRawValue = attachments.first?[.status] as? Int, let status = SCFrameStatus(rawValue: statusRawValue), status == .complete else { return } self.trackFrameRate() self.handleFrame(sampleBuffer) } do { try stream?.addStreamOutput(screenStreamOutput!, type: .screen, sampleHandlerQueue: streamOutputQueue) stream?.startCapture { [weak self] error in print("[DEBUG] SCStream.startCapture completion handler.") guard error == nil else { print("[DEBUG] Failed to start capture: \(error!.localizedDescription)") self?.handleStreamError(error!) return } DispatchQueue.main.async { self?.isRecording = true self?.isStreamActive = true // Update state on successful start print("[DEBUG] Recording started. isRecording = true.") } } } catch { print("[DEBUG] Error adding stream output: \(error.localizedDescription)") handleStreamError(error) } } private func handleFrame(_ sampleBuffer: CMSampleBuffer) { rollingFrameBufferQueue.async { [weak self] in guard let self = self else { return } let pts = CMSampleBufferGetPresentationTimeStamp(sampleBuffer) var retainedBuffer: CMSampleBuffer? CMSampleBufferCreateCopy(allocator: kCFAllocatorDefault, sampleBuffer: sampleBuffer, sampleBufferOut: &retainedBuffer) guard let buffer = retainedBuffer else { print("[DEBUG] Failed to copy sample buffer") return } self.rollingFrameBuffer.append((buffer, pts)) if let lastPTS = self.rollingFrameBuffer.last?.1 { while let firstPTS = self.rollingFrameBuffer.first?.1, CMTimeGetSeconds(CMTimeSubtract(lastPTS, firstPTS)) > self.rollingBufferDuration { self.rollingFrameBuffer.removeFirst() } } } } func stream(_ stream: SCStream, didStopWithError error: Error) { print("[DEBUG] Stream stopped with error: \(error.localizedDescription)") displayCheckQueue.async { [weak self] in // Move to displayCheckQueue for synchronization self?.handleStreamError(error) } } what could be the reason for this and what would be the possible fix logically? i dont understand why it's dependant on queueDepth, and if it is, how can I empty and append new recorded frames to it so that it continues working? any help or resource is greatly appreciated!

I developed an educational app that implements audio-video communication through RTC, while using WebView to display course materials during classes. However, some users are experiencing an issue where the audio playback from WebView is very quiet. I've checked that the AVAudioSessionCategory is set by RTC to AVAudioSessionCategoryPlayAndRecord, and the AVAudioSessionCategoryOption also includes AVAudioSessionCategoryOptionMixWithOthers. What could be causing the WebView audio to be suppressed, and how can this be resolved?

We found that on some iPad devices (such as iPad8,9/iPad OS/18.5), when the media is playing, the recorded human voice is very small and is basically suppressed by the sound of the playing media. When the media is not playing, the human voice can be recorded. Likely when use screen recording with microphone, the ambient sound is also basically suppressed by the media sound.

Hi all, I'm capturing a photo using AVCapturePhotoOutput, and I've set: let photoSettings = AVCapturePhotoSettings() photoSettings.isDepthDataDeliveryEnabled = true Then I create the handler like this: let data = photo.fileDataRepresentation() let handler = try ImageRequestHandler(data: data, orientation: .right) Now I’m wondering: If depth data delivery is enabled, is it actually included and used when I pass the Data to ImageRequestHandler? Or do I need to explicitly pass the depth data using the other initializer? let handler = try ImageRequestHandler( cvPixelBuffer: photo.pixelBuffer!, depthData: photo.depthData, orientation: .right ) In short: Does ImageRequestHandler(data:) make use of embedded depth info from AVCapturePhoto.fileDataRepresentation() — or is the pixel buffer + explicit depth data required? Thanks for any clarification!

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?

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() } } }

Hi all, I'm working on an audio visualizer app that plays files from the user's music library utilizing MediaPlayer and AVAudioEngine. I'm working on getting the music library functionality working before the visualizer aspect. After setting up the engine for file playback, my app inexplicably crashes with an EXC_BREAKPOINT with code = 1. Usually this means I'm unwrapping a nil value, but I think I'm handling the optionals correctly with guard statements. I'm not able to pinpoint where it's crashing. I think it's either in the play function or the setupAudioEngine function. I removed the processAudioBuffer function and my code still crashes the same way, so it's not that. The device that I'm testing this on is running iOS 26 beta 3, although my app is designed for iOS 18 and above. After commenting out code, it seems that the app crashes at the scheduleFile call in the play function, but I'm not fully sure. Here is the setupAudioEngine function: private func setupAudioEngine() { do { try AVAudioSession.sharedInstance().setCategory(.playback, mode: .default) try AVAudioSession.sharedInstance().setActive(true) } catch { print("Audio session error: \(error)") } engine.attach(playerNode) engine.attach(analyzer) engine.connect(playerNode, to: analyzer, format: nil) engine.connect(analyzer, to: engine.mainMixerNode, format: nil) analyzer.installTap(onBus: 0, bufferSize: 1024, format: nil) { [weak self] buffer, _ in self?.processAudioBuffer(buffer) } } Here is the play function: func play(_ mediaItem: MPMediaItem) { guard let assetURL = mediaItem.assetURL else { print("No asset URL for media item") return } stop() do { audioFile = try AVAudioFile(forReading: assetURL) guard let audioFile else { print("Failed to create audio file") return } duration = Double(audioFile.length) / audioFile.fileFormat.sampleRate if !engine.isRunning { try engine.start() } playerNode.scheduleFile(audioFile, at: nil) playerNode.play() DispatchQueue.main.async { [weak self] in self?.isPlaying = true self?.startDisplayLink() } } catch { print("Error playing audio: \(error)") DispatchQueue.main.async { [weak self] in self?.isPlaying = false self?.stopDisplayLink() } } } Here is a link to my test project if you want to try it out for yourself: https://github.com/aabagdi/VisualMan-example Thanks!

Hello everyone, I'm working on a feature where I need to capture the highest possible quality photo (e.g., 24MP on supported devices) and upload it to our server. I don't need the photos to appear in user's main Photos app so I thought I could store the photos in app's private directory using FileManager until they are uploaded. This wouldn't require requesting Photo Library permission, maximizing user privacy. The documentation on AVCapturePhotoOutput states that "the 24MP setting (5712, 4284) is only serviced as 24MP when opted-in to autoDeferredPhotoDeliveryEnabled" /** @property maxPhotoDimensions @abstract Indicates the maximum resolution of the requested photo. @discussion Set this property to enable requesting of images up to as large as the specified dimensions. Images returned by AVCapturePhotoOutput may be smaller than these dimensions but will never be larger. Once set, images can be requested with any valid maximum photo dimensions by setting AVCapturePhotoSettings.maxPhotoDimensions on a per photo basis. The dimensions set must match one of the dimensions returned by AVCaptureDeviceFormat.supportedMaxPhotoDimensions for the current active format. Changing this property may trigger a lengthy reconfiguration of the capture render pipeline so it is recommended that this is set before calling -[AVCaptureSession startRunning]. Note: When supported, the 24MP setting (5712, 4284) is only serviced as 24MP when opted-in to autoDeferredPhotoDeliveryEnabled. */ @available(iOS 16.0, *) open var maxPhotoDimensions: CMVideoDimensions (btw. this note is not present in the docs https://developer.apple.com/documentation/avfoundation/avcapturephotooutput/maxphotodimensions) Enabling autoDeferredPhotoDeliveryEnabled means that for a 24MP capture, the system will call the photoOutput(_:didFinishCapturingDeferredPhotoProxy:error:) delegate method, providing a proxy object instead of the final image data. According to the WWDC23 session "Create a more responsive camera experience," this AVCaptureDeferredPhotoProxy must be saved to the PHPhotoLibrary using a PHAssetCreationRequest with the resource type .photoProxy. The system then handles the final processing in the background within the library. To use deferred photo processing, you'll need to have write permission to the photo library to store the proxy photo, and read permission if your app needs to show the final photo or wants to modify it in any way. https://developer.apple.com/videos/play/wwdc2023/10105/?time=799 This seems to create a hard dependency on the Photo Library for accessing 24MP images. My question is: Is there any way to receive the final, processed 24MP image data directly in the app after a deferred capture, without using PHPhotoLibrary as the processing intermediary? For example, is there a delegate callback or a mechanism I'm missing that provides the final data for a deferred photo, allowing an app to handle it in-memory or in its own private sandbox, completely bypassing the user's Photo Library? Our goal is to follow Apple's privacy-first principles by avoiding requesting a PHPhotoLibrary authorization when our app's core function doesn't require access to the user's photo collection. Thank you for your time and any clarification you can provide.

In iOS 26, AVSpeechSynthesizer read Mandarin into Cantonese pronunciation. No matter how you set the language, and change the settings of my phone system, it doesn't work. let utterance = AVSpeechUtterance(string: "你好啊") //let voice = AVSpeechSynthesisVoice(language: "zh-CN") // not work let voice = AVSpeechSynthesisVoice(language: "zh-Hans") // not work too utterance.voice = voice et synth = AVSpeechSynthesizer() synth.speak(utterance)

AVCaptureVideoDataOutput.preparesCellularRadioForNetworkConnection requires com.apple.developer.avfoundation.video-data-output-prepares-cellular-radio-for-machine-readable-code-scanning. But I cannot acquire its entitlement. I can't find its entitlement on 'Certificates, Identifiers &amp; Profiles'. Any solutions? Provisioning profile "iOS Team Provisioning Profile: ......" doesn't include the com.apple.developer.avfoundation.video-data-output-prepares-cellular-radio-for-machine-readable-code-scanning entitlement.

During the Camera lab session at WWDC25, support for DICOM was mentioned. I'm trying to work with the new AVFileType dcm to help with handling DICOM scans. Can anyone provide some assistance?

it will use about 300MB memory, it cause a memory peak

Issue: After iOS 18.5 release, our app is experiencing a significant increase in AVCaptureSessionInterruptionReason.videoDeviceNotAvailableWithMultipleForegroundApps errors. Details: Our camera-related code has not been updated recently.However, we've observed that the error rate has significantly increased starting from May 2025. The error rate has risen from approximately 0.02% (2 in 10,000 users) to 0.1% (1 in 1,000 users). This represents a 5x increase in error occurrence. The frequency has increased noticeably since iOS 18.5 This is affecting our app's camera functionality and user experience Questions: Are there any known changes in iOS 18.5 regarding camera access management? What are the recommended best practices to handle this interruption reason? Are there any API changes we should be aware of? Best, Shay

Hi Apple Developer Team, I'm encountering a regression in iOS 18 related to the Picture-in-Picture (PiP) feature when using custom views. In previous versions of iOS (up to iOS 17), it's possible to show a custom UIView inside the PiP window — for example, a UILabel, UITableView, or other standard UI elements. This works well even when switching between apps. However, in iOS 18 (tested on the developer beta), there's an issue: If App A starts PiP mode and displays a custom view, and then the user switches to App B and starts a video call (e.g., using FaceTime or another VoIP app), all the custom views in the PiP window suddenly disappear. The PiP window itself remains, but its contents are empty. This behavior did not occur in earlier iOS versions. Steps to reproduce: In App A, start Picture-in-Picture with a custom UIView added to the PiP window. Switch to App B and initiate a video call (e.g., FaceTime). Observe the PiP window — the custom view is no longer visible. This issue breaks UI functionality that previously worked and may impact apps that rely on interactive or dynamic content in PiP. Is this a known issue in iOS 18, or is this behavior change intentional? Any suggested workarounds or updates? Thanks in advance for your support.

AVCaptureSession's startRunning method is thread blocking and seems to be slow. What is this method doing behind the scenes? For context: I'm working on Simulator Camera support and I have a 'fake' AVCaptureDevice that might be causing this. My hypothesis is that AVCaptureSession tries to connect to the device and waits for a notification to be posted back. I'd love to find a way to let my fake device message AVCaptureSession that it's connected.

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

Before you post —Camera doesn't work on the Simulator— that's no longer true. I've made a solution that makes the Simulator believe there's an actual hardware device connected, allowing users to stream the macOS camera to the iOS Simulator (see for more info RocketSim's documentation: https://docs.rocketsim.app/features/hzQMSrSga7BGWvxdNVdwYs/simulator-camera-support/58tQ5jvevLNSnyUEA7VgAv) Now, it works for VNDocumentCameraViewController, but when I try opening DataScannerViewController, I directly run into: Failed to start scanning: The operation couldn’t be completed. (VisionKit.DataScannerViewController.ScanningUnavailable error 0.) My question: How does this view controller determine whether scanning is available? Is there a certain capability the available AVCaptureDevice's need to support maybe? Any direction would be helpful for me to make this work for developers, making them build apps faster!

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!