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Why personal music recommendations contain no more than 12 item?
Hi! I get personal recommendations MusicItemCollection using this code: func getRecommendations() async throws -> MusicItemCollection<MusicPersonalRecommendation> { let request = MusicPersonalRecommendationsRequest() let response = try await request.response() let recommendations = response.recommendations return recommendations } However, all recommendations contain no more than 12 MusicItem's, while the Music.app application provides much more for some recommendations, for example, for the You recently listened recommendation, the Music.app application displays 40 items. Each recommendation has an items property that contains a collection of musical items MusicItemCollection<MusicPersonalRecommendation.Item>, the hasNextBatch property for these collections is always false. I expected that for some collections loading of new items would be available. Please tell me if I'm doing something wrong or is this a MusicKit bug? Thank you!
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479
Feb ’25
AVPlayer error: Too many open files
For some users in production, there's a high probability that after launching the App, using AVPlayer to play any local audio resources results in the following error. Restarting the App doesn't help. issue: [error: Error Domain=AVFoundationErrorDomain Code=-11800 "这项操作无法完成" UserInfo={NSLocalizedFailureReason=发生未知错误(24), NSLocalizedDescription=这项操作无法完成, NSUnderlyingError=0x30311f270 {Error Domain=NSPOSIXErrorDomain Code=24 "Too many open files"}} I've checked the code, and there aren't actually multiple AVPlayers playing simultaneously. What could be causing this?
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434
Feb ’25
Build a vision capture system for apple vision pro
Hi, I am a newbie here. We have been given a task to build a robotic vision system to capture an immersive video in a hazed environment, which will later be played on Apple Vision Pro. I am thinking of starting with 2 or 4 basic CMOS camera sensors, such as IMX378, AR0144, or VD66GY, and designing an FPGA-based circuit to synchronously capture and store raw frame-by-frame data. Some frame initial processing such as demosaicing and filtering can also be done by the FPGA. Then, I would use software for post-processing to convert the data into a compatible video format for Apple Vision Pro. Will this idea work? I can handle the raw data capture, but I’m unsure if this approach is feasible and what post-processing software I should use. Thanks a lot for your suggestions! Charlie
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334
Feb ’25
How to write RGB & Depth Frames Without Losing Synchronization
I’m currently working on a project where I capture both depth frames and RGB frames using AVCaptureDataOutputSynchronizer. Depth frames are stored as raw binary data and RGB frames are saved with AVAssetWriter. The issue I’m facing is that AVAssetWriter enforces a fixed framerate, meaning it adds or discards frames to maintain that rate (as I understand it). This causes a desynchronization between the depth and RGB frames, which is a problem because I need each depth frame to be exactly matched with the corresponding RGB frame as they were captured. How can I ensure that the RGB frames are saved without AVAssetWriter modifying the frame count?
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390
Feb ’25
Music Keeps cutting off
Everytime I put my AirPods in and connect them to my phone or my Mac or my iPad since the iOS 18.3 update on my devices they’ve been disconnecting without reason, pausing songs I’m in the middle of playing, and only partially reconnecting in one pod and it’s getting really frustrating
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320
Feb ’25
Does PHAsset localIdentifier change after device transfer?
Hi, I’m working on a photo backup app. I track the PHAsset localIdentifier to determine which photos have been backed up and which haven’t. Recently, I’ve noticed that two users seem to have experienced the localIdentifier changes after transferring data to a new iPhone using Quick Start. Additionally, others on StackOverflow have mentioned that the localIdentifier sometimes changes after updating the iOS version. https://stackoverflow.com/questions/40094728/phobject-localidentifier-reliability I’d like to confirm the reliability of the localIdentifier after an iOS version upgrade or device transfer. Can I continue using these locally stored localIdentifiers? Or is there another recommended approach, such as using PHCloudIdentifier?
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398
Feb ’25
Unkown photos were added to my iPhone Photo App.
There are several unknown pictures were added to my iPhone Photos. I'm developing a iOS app in swiftUI. And I'm sure that neither my developing app asked a permission to save photos to iOS device, nor these pictures are taken by myself, downloaded from the web, or synced from my iCloud. Why does this happen? Is my account or my iPhone attacked or hacked? btw, my device has turned the debug mode on, will this setting option would leads some vulnerability or some debug tools would add photos to my albums? The attached pictures are the unknown photos in my Photos App. I'v search this photo with google. And I found that many developers in stack overflow use this picture when they encounter troubles with image display or other manipulation. Where where are this photo come from? Why does it exist in my Photo albums?
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485
Feb ’25
Musickit Media player missing output device selection
Hi All, I am working on a DJ playout app (MACOS). The app has a few AVAudioPlayerNode's combined with the ApplicationMusicPlayer from Musickit. I can route the output of the AVaudioPlayer to a hardware device so that the audio files are directed to their own dedicated output on my Mac. The ApplicationMusicPlayer is following the default output and this is pretty annoying. Has anyone found a solution to chain the ApplicationMusicPlayer and get it set to a output device? Thanks Pancras
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600
Feb ’25
Reference White Calculation for HDR Video Rendering in Metal
Our multimedia application Boinx FotoMagico displays media files of various kinds with a Metal rendering engine. At the moment we still use .bgra8Unorm pixel format and sRGB color space and only render in SDR, which is increasingly a problem, as much of the video content is HDR nowadays (e.g. videos shot on an iPhone). For that reason we would like to switch to EDR rendering with .rgba16Float pixel format and extendedLinearDisplayP3 color space. We have already worked out how to do this for HDR image files, but still have a technical problem when rendering HDR video files. We are using AVFoundation to get the video frames as CVPixelBuffers and convert them to MTLTexture using a CVMetalTextureCache. MTLTextures are then further processed in various compute shaders before being rendered to screen. However the pixel values in the texture are not what we expected. Video frames appear too bright/overexposed. In WWDC21 session "Explore HDR rendering with EDR" Ken Greenebaum mentioned: “AVFoundation does not presently decode HDR formats, such as HDR10, to EDR. Consequently, these need to be adapted for use with EDR rendering. This conversion is straightforward and involves two steps. First, converting to linear light by applying the inverse transfer function. And second, dividing by the medium's reference white.” https://developer.apple.com/videos/play/wwdc2021/10161?time=1498 However, the session does not explain, how to get or calculate the correct value for "reference white". We could not find any relevant info on the web. This is why we need DTS assistance. We need the code that calculates the correct value for reference white for any kind of video, whether it is SDR or HDR, and regardless of codec and encoding. I assume that Ken Greenebaum is the best Apple engineer to ask in this case, because he recorded most of the EDR related WWDC sessions in recent years? We have written a small test app that renders a short sample video (HLG encoding). The window contains two views. The upper view uses an AVPlayerLayer and renders the video natively just like QuickTime Player. The video content looks correct here. BTW, the window background is SDR white, so that bright EDR pixels can be clearly identified, e.g. the clouds just above the mountains in the upper left corner of the sample video. You may need to lower display brightness a bit if these clouds do not appear brighter than the white window background. The bottom view uses a CAMetalLayer and low-level Metal rendering. The CVPixelBuffers we receive from AVFoundation still need to be scaled down so that SDR reference white reaches pixel value 1.0. Entering a value of 9.0 to 10.0 for reference white in the text field makes it look about right on my Studio Display. But that is just experimental for this sample video file. We need code to calculate the correct value for reference white for any kind of video file! We have a couple of questions: SDR videos should probably use 1.0 as reference white, as their encoded pixel values can already be used as is? Is this assumption correct? Different video encoding of HDR video (HLG, PQ, etc) will probably lead to different values for reference white? Is the value for reference white constant throughout a video, or can it vary over time, either scene by scene, or even frame by frame? If it can vary, does the CVPixelBuffer of the current video frame contain all the necessary metadata to calculate the correct value? Does the NSScreen.maximumExtendedDynamicRangeColorComponentValue also influence the reference white value? The attached sample project is structured in a way that the only piece of code that needs to be modified is the ViewController.sdrReferenceWhiteValue() function. Please read the comments and the #warning in this function. This is where the code for calculating the reference white value should be inserted. Here is the download link for the sample project: https://www.dropbox.com/scl/fi/4w5gmftav5xhbixu9u6pb/HDRMetalTest.zip?rlkey=n8cm02soux3rx03vplgo6h1lm&dl=0
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Feb ’25
HDR10 MVHECV can not play on Safari
Hi, just generated a HDR10 MVHEVC file, mediainfo is below: Color range : Limited Color primaries : BT.2020 Transfer characteristics : PQ Matrix coefficients : BT.2020 non-constant Codec configuration box : hvcC+lhvC then generate the segment files with below command: mediafilesegmenter --iso-fragmented -t 4 -f av_1 av_new_1.mov then upload the segment files and prog_index.m3u8 to web server. just find that can not play the HLS stream on Safari... the url is http://ip/vod/prog_index.m3u8 just checked that if i remove the tag Transfer characteristics : PQ when generating the MVHEVC file. above same mediafilesegmenter command and upload the files to web server. the new version of HLS stream is can play on Safari... Is there any way to play HLS PQ video on Safari. thanks.
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Feb ’25
Multiview HLS with HDR
I have an HDR10+ encoded video that if loaded as a mov plays back on the Apple Vision Pro but when that video is encoded using the latest (1.23b) Apple HLS tools to generate an fMP4 - the resulting m3u8 cannot be played back in the Apple Vision Pro and I only get back a "Cannot Open" error. To generate the m3u8, I'm just calling mediafilesegmenter (with -iso-fragmented) and then variantplaylistcreator. This completes with no errors but the m3u8 will playback on the Mac using VLC but not on the Apple Vision Pro. The relevant part of the m3u8 is: #EXT-X-STREAM-INF:AVERAGE-BANDWIDTH=40022507,BANDWIDTH=48883974,VIDEO-RANGE=PQ,CODECS="ec-3,hvc1.1.60000000.L180.B0",RESOLUTION=4096x4096,FRAME-RATE=24.000,CLOSED-CAPTIONS=NONE,AUDIO="audio1",REQ-VIDEO-LAYOUT="CH-STEREO" {{url}} Has anyone been able to use the HLS tools to generate fMP4s of MV-HEVC videos with HDR10?
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1.1k
Feb ’25
How to receive AVMetricEvent performance data?
I am would like to look at AVMetricEvent data during video playback, so I have added this code to a test video player app: let playerItem: AVPlayerItem = ... let allMetrics = playerItem.allMetrics() Task.init { print("metrics task started") do { for try await metricEvent in allMetrics { print("metric event: \(metricEvent.description)") } } catch { print("unexpected metric iterator error \(error)") } } Running this in Simulator on iPhone 16 Pro (18.0) does not result in any "metric event" diagnostic messages being printed when the video associated with this AVPlayerItem is playing. Only the "metric task started" diagnostic message is seen. What am I doing wrong that prevents metric data being received?
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Feb ’25
On iOS 18, Mandarin is read aloud as Cantonese
Please include the line below in follow-up emails for this request. Case-ID: 11089799 When using AVSpeechUtterance and setting it to play in Mandarin, if Siri is set to Cantonese on iOS 18, it will be played in Cantonese. There is no such issue on iOS 17 and 16. 1.let utterance = AVSpeechUtterance(string: textView.text) let voice = AVSpeechSynthesisVoice(language: "zh-CN") utterance.voice = voice 2.In the phone settings, Siri is set to Cantonese
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568
Feb ’25
3D scanning and 3D model with texture mapping
I am new here and would appreciate help in coding or an explanation what to use in swift for an app which will be able to capture LiDAR scanning and RGB data from taken pictures, generate a 3D mesh, and create .OBJ, .MTL, and .JPEG file set for further manipulation of 3D model. I am able to create from LiDAR scanning 3D mesh and .OBJ file but can not generate .MTL and .JPEG for a texture of 3D model.
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426
Feb ’25
[Crash Report] PHAssetResourceManager.writeDataForAssetResource causes app crash on iOS18
We are encountering a critical, intermittently occurring crash issue when accessing photo data using PHAssetResourceManager.writeDataForAssetResource on iOS 18. The problem does not arise on iOS 17 or earlier versions. We have been unable to identify a consistent reproduction path. Based on user feedback, the issue seems to involve Live Photo and Raw image files. Our investigation has revealed that the crash occurs in the +[PISchema identifier] method of the PhotoImaging Framework. When called manually, this method causes a crash on iOS 18 but works without issues on iOS 17. Reproduction Steps: 1.Fetch PHAsset. 2.Get PHAssetResource by [PHAssetResource assetResourcesForAsset:]. 3.Call [PHAssetResourceManager writeDataForAssetResource:toFile:options:completionHandler:]. Crash Log: Incident Identifier: CFD60092-FDB1-43B4-BA42-3F507F7B8B96 CrashReporter Key: 260b4780989083a54e0cb451930fe9a3bed64862 Hardware Model: iPhone13,4 AppStoreTools: 16C5031b AppVariant: 1:iPhone13,4:18 Code Type: ARM-64 (Native) Role: Foreground Parent Process: launchd [1] Date/Time: 2025-02-15 19:07:57.7054 +0800 Launch Time: 2025-02-15 19:07:55.4106 +0800 OS Version: iPhone OS 18.3.1 (22D72) Release Type: User Baseband Version: 5.20.03 Report Version: 104 Exception Type: EXC_CRASH (SIGABRT) Exception Codes: 0x0000000000000000, 0x0000000000000000 Termination Reason: SIGNAL 6 Abort trap: 6 Terminating Process: mCloud_iPhone [11109] Triggered by Thread: 11 Application Specific Information: abort() called Thread 11 name: Dispatch queue: com.apple.NSXPCConnection.m-user.com.apple.photos.service Thread 11 Crashed: 0 libsystem_kernel.dylib 0x1e850b2d4 __pthread_kill + 8 1 libsystem_pthread.dylib 0x221b4959c pthread_kill + 268 2 libsystem_c.dylib 0x19ec24b08 abort + 128 3 NeutrinoCore 0x1bdcdbdec -[NUAssertionPolicyAbort notifyAssertion:] + 68 4 NeutrinoCore 0x1bdcdbbf4 -[NUAssertionPolicyComposite notifyAssertion:] + 160 5 NeutrinoCore 0x1bdcdc098 -[NUAssertionPolicyUnique notifyAssertion:] + 176 6 NeutrinoCore 0x1bdcdb524 -[NUAssertionHandler handleFailureInFunction:file:lineNumber:currentlyExecutingJobName:description:arguments:] + 156 7 NeutrinoCore 0x1bdcdc4bc _NUAssertFailHandler + 176 8 NeutrinoCore 0x1bdc8ea98 -[NUIdentifier initWithNamespace:name:version:] + 2352 9 NeutrinoCore 0x1bdc8eba8 -[NUIdentifier initWithName:version:] + 84 10 NeutrinoCore 0x1bdc8ec10 -[NUIdentifier initWithName:] + 68 11 PhotoImaging 0x1bda54ce4 +[PISchema identifier] + 36 12 PhotoImaging 0x1bda550fc +[PISchema registeredPhotosSchemaIdentifier] + 32 13 PhotoImaging 0x1bd9d7128 +[PIPhotoEditHelper newComposition] + 28 14 PhotoImaging 0x1bd940798 +[PICompositionSerializer deserializeCompositionFromAdjustments:metadata:formatIdentifier:formatVersion:sidecarData:error:] + 160 15 PhotoImaging 0x1bd9412ec +[PICompositionSerializer deserializeCompositionFromData:formatIdentifier:formatVersion:sidecarData:error:] + 224 16 PhotoLibraryServices 0x1afabf75c -[PLPhotoEditPersistenceManager loadCompositionFrom:formatIdentifier:formatVersion:sidecarData:error:] + 1856 17 PhotoLibraryServices 0x1afabffe4 +[PLPhotoEditPersistenceManager validateAdjustmentData:formatIdentifier:formatVersion:error:] + 108 18 Photos 0x1af4ac360 __167+[PHContentEditingInputRequestContext contentEditingInputRequestContextForAsset:requestID:managerID:networkAccessAllowed:downloadIntent:progressHandler:resultHandler:]_block_invoke + 260 19 Photos 0x1af4ac67c -[PHAdjustmentData(ContentEditingInput) _contentEditing_readableByClientWithVerificationBlock:] + 136 20 Photos 0x1af4ac4b0 -[PHAdjustmentData(ContentEditingInput) _contentEditing_requiredBaseVersionReadableByClient:verificationBlock:] + 88 21 Photos 0x1af4abb8c -[PHContentEditingInputRequestContext _adjustmentBaseVersionFromResult:request:canHandleAdjustmentData:] + 404 22 Photos 0x1af4a911c -[PHContentEditingInputRequestContext produceChildRequestsForRequest:reportingIsLocallyAvailable:isDegraded:result:] + 624 23 Photos 0x1af2c1d10 -[PHMediaRequestContext _produceChildRequestsForRequest:withResult:] + 88 24 Photos 0x1af2c11e8 -[PHMediaRequestContext mediaRequest:didFinishWithResult:] + 88 25 Photos 0x1af505184 -[PHAdjustmentDataRequest _finishFromAsynchronousCallback] + 124 26 Photos 0x1af5050a0 __39-[PHAdjustmentDataRequest startRequest]_block_invoke + 584 27 PhotoLibraryServicesCore 0x1b001be8c __106-[PLAssetsdResourceClient adjustmentDataForAsset:networkAccessAllowed:trackCPLDownload:completionHandler:]_block_invoke.86 + 864 28 CoreFoundation 0x196dd8e34 __invoking___ + 148 29 CoreFoundation 0x196dd7e7c -[NSInvocation invoke] + 428 30 Foundation 0x195a64ae0 __NSXPCCONNECTION_IS_CALLING_OUT_TO_EXPORTED_OBJECT__ + 16 31 Foundation 0x195a63514 -[NSXPCConnection _decodeAndInvokeReplyBlockWithEvent:sequence:replyInfo:] + 532 32 Foundation 0x195a6653c __88-[NSXPCConnection _sendInvocation:orArguments:count:methodSignature:selector:withProxy:]_block_invoke_5 + 188 33 libxpc.dylib 0x221babb80 _xpc_connection_reply_callout + 116 34 libxpc.dylib 0x221b9e2d0 _xpc_connection_call_reply_async + 80 35 libdispatch.dylib 0x19eb6b028 _dispatch_client_callout3 + 20 36 libdispatch.dylib 0x19eb88b64 _dispatch_mach_msg_async_reply_invoke + 340 37 libdispatch.dylib 0x19eb7242c _dispatch_lane_serial_drain + 352 38 libdispatch.dylib 0x19eb73158 _dispatch_lane_invoke + 432 39 libdispatch.dylib 0x19eb7e38c _dispatch_root_queue_drain_deferred_wlh + 288 40 libdispatch.dylib 0x19eb7dbd8 _dispatch_workloop_worker_thread + 540 41 libsystem_pthread.dylib 0x221b44680 _pthread_wqthread + 288 42 libsystem_pthread.dylib 0x221b42474 start_wqthread + 8
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398
Feb ’25
[Fairplay Streaming] Time Manipulation Detection DRM License Servers
Our team conducted security testing and found one vulnerability with fairplay license acquisition. Our QA engineer manually changed the device's system date and time (setting it 4 days into the future) and was able to successfully obtain a license response and initiate playback on an iOS device. However, on an Android device, the license acquisition failed. Can you please tell us if Time Manipulation Detection is available in FairPlay SDK?
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435
Feb ’25
Can we say that HLS uses UDP?
Hello, Apple video engineers. According to the official documentation, HLS is built on HTTP and traditionally ran on top of TCP. However, with the introduction of HTTP/3, which uses QUIC (runs on top of UDP), I would like to clarify the following: Has the official HLS specification changed in a way that allows it to be considered UDP-based when using HTTP/3? And is it fair to say that HLS supports UDP since the transport can go over HTTP/3 and QUIC? Would it be more accurate to say that HLS remains HTTP-dependent, and the transport protocol (TCP or QUIC) only determines how HTTP requests are delivered? My thoughts: Since HTTP/3 uses QUIC running over UDP, we still can't say that HLS supports UDP in a classical way, as it is introduced in RTP, RTSP, SRT.
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434
Feb ’25
PHPickerViewController update preselectedAssetIdentifiers
I am trying to recreate the iOS Messages app photo selection UI, where a PHPickerViewController is displayed half screen, with the message text field and a scrolling photo viewer on top. I have that UI mostly working, but cannot figure out how to allow a user to remove an image from my scrolling photo viewer (just like in the iOS Messages app). When the picker is initially displayed, I can show selected images using the preselectedAssetIdentifiers. However, if the user taps the "x" to remove an image from the scrolling photo viewer, there is no way that I have found to update that selection in the picker. I can dismiss/show a new picker with the animated property set to false, but that creates a very apparent bounce in the screen. Are there any ways I am missing to accomplish this? Here is what I have so far:
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425
Feb ’25
MacOS: AudioUnit packaged as .appex won't load when host app is sandboxed
Hi, I'm working on an audio mixing app, that comes with bundled audio units that provide some of the app's core functionality. For the next release of that app, we are planning to make two changes: make the app sandboxed package the bundled audio units as .appex bundles instead as .component bundles, so we don't need to take care of the installation at the correct spot in the file system When trying this new approach, we run into problems where [[AVAudioUnitEffect alloc] initWithAudioComponentDescription:] crashes when trying to load our audio unit with the exception: AVAEInternal.h:109 [AUInterface.mm:468:AUInterfaceBaseV3: (AudioComponentInstanceNew(comp, &_auv2)): error -10863 Our audio unit has the `sandboxSafe flag enabled, and loads fine when the host app is not sandboxed, so I'm guessing I got the bundle id/code signing requirements for the .appex correct. It seems, that my .appex isn't even loaded, and the system rejects it because of its metadata. Maybe there something wrong the Info.plist generated by Juice? "BuildMachineOSBuild" => "23H222" "CFBundleDisplayName" => "elgato_sample_recorder" "CFBundleExecutable" => "ElgatoSampleRecorder" "CFBundleIdentifier" => "com.iwascoding.EffectLoader.samplerecorderAUv3" "CFBundleName" => "elgato_sample_recorder" "CFBundlePackageType" => "XPC!" "CFBundleShortVersionString" => "1.0.0.0" "CFBundleSignature" => "????" "CFBundleSupportedPlatforms" => [ 0 => "MacOSX" ] "CFBundleVersion" => "1.0.0.0" "DTCompiler" => "com.apple.compilers.llvm.clang.1_0" "DTPlatformBuild" => "24C94" "DTPlatformName" => "macosx" "DTPlatformVersion" => "15.2" "DTSDKBuild" => "24C94" "DTSDKName" => "macosx15.2" "DTXcode" => "1620" "DTXcodeBuild" => "16C5032a" "LSMinimumSystemVersion" => "10.13" "NSExtension" => { "NSExtensionAttributes" => { "AudioComponents" => [ 0 => { "description" => "Elgato Sample Recorder" "factoryFunction" => "elgato_sample_recorderAUFactoryAUv3" "manufacturer" => "Manu" "name" => "Elgato: Elgato Sample Recorder" "sandboxSafe" => 1 "subtype" => "Znyk" "tags" => [ 0 => "Effects" ] "type" => "aufx" "version" => 65536 } ] } "NSExtensionPointIdentifier" => "com.apple.AudioUnit-UI" "NSExtensionPrincipalClass" => "elgato_sample_recorderAUFactoryAUv3" } "NSHighResolutionCapable" => 1 } Any ideas what I am missing?
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484
Feb ’25