the problem is when using HLS live stream with AVPlayer on iOS/ tvOS the player chooses first highest bandwidth then slowly steps down to lowest (within 1-3min) and eventually steps up again then repeats to step down.
the AVPlayer error log sends events:
errorStatusCode: -12888, errorDomain: Optional("CoreMediaErrorDomain"), errorComment: Optional("The operation couldn't be completed. (CoreMediaErrorDomain error -12888 - Playlist File unchanged for longer than 1.5 * target duration
we use standard segments in CMAF format, 2sec duration
#EXTM3U
#EXT-X-VERSION:6
#EXT-X-TARGETDURATION:2
#EXT-X-MEDIA-SEQUENCE:147065903
#EXT-X-MAP:URI="video_1_4660000_init.mp4?device_profile=cmaf_cbcs_verimatrix_cei%26seg_size=2%26cmaf=2"
#EXT-X-PROGRAM-DATE-TIME:2025-04-30T12:51:07
#EXTINF:2.000,
video_1_4660000_t17460174670001555.mp4?device_profile=cmaf_cbcs_verimatrix_cei%26seg_size=2%26cmaf=2
#EXTINF:2.000,
video_1_4660000_t17460174690001555.mp4?device_profile=cmaf_cbcs_verimatrix_cei%26seg_size=2%26cmaf=2
#EXTINF:2.000,
video_1_4660000_t17460174710001555.mp4?device_profile=cmaf_cbcs_verimatrix_cei%26seg_size=2%26cmaf=2
when using 6sec segments the player stays stable at highest bandwidth.
is there a way to avoid this error? in AVPlayer or HLS configuration?
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TL;DR How to solve possible racing issue of EXT-X-SESSION-KEY request and encrypted media segment request?
I'm having trouble using custom AVAssetResourceLoaderDelegate with video manifest containing VideoProtectionKey(VPK). My master manifest contains rendition manifest url and VPK url. When not using custom resource delegate, everything works fine.
My custom resource delegate is implemented in way where it first append prefix to scheme of the master manifest url before creating the asset. And during handling master manifest, it puts back original scheme, make the request, modify the scheme for rendition manifest url in the response content by appending the same prefix again, so that rendition manifest request also goes into custom resource loader delegate. Same goes for VPK request. The AES-128 key is stored in memory within custom resource loader delegate object. So far so good.
The VPK is requested before segment request. But the problem comes where the media segment requests happen. The media segment request url from rendition manifest goes into custom resource loader as well and those are encrypted. I can see segment request finish first then the related VPK requests kick in after a few seconds. The previous VPK value is cached in memory so it is not network causing the delay but some mechanism that I'm not aware of causing this.
So could anyone tell me what would be the proper way of handling this situation? The native library is handling it well so I just want to know how. Thanks in advance!
Hi everyone,
We’re currently developing a music-based app using MusicKit, and we recently noticed that iOS 26 beta introduces a new “Automix” feature in the Apple Music app. This enables seamless DJ-style transitions between songs—beyond the standard crossfade functionality.
We’re trying to understand:
Will this Automix feature be accessible to third-party apps that use MusicKit?
If not available in the initial iOS 26 release, is there a plan to expose it through public APIs in a future update?
Is there any technical documentation, WWDC session, or roadmap info regarding Automix support via MusicKit?
This functionality would be a significant enhancement for our app, especially for intelligent audio transitions and curated playlists.
Thanks.
The documentation for the Apple Music API indicates that the genreNames field for a given artist (see https://developer.apple.com/documentation/applemusicapi/artists/attributes-data.dictionary) is an array of strings. However, it only appears as though you return ONE SINGLE GENRE per Artist, regardless of how many genres might be attached to that artist's albums.
Am I missing something? Is there an artist where multiple genres may be returned, or is this a bug in the documentation?
Hi everyone,
I noticed that Apple recently added a few new beta sample codes related to video encoding:
Encoding video for low-latency conferencing
Encoding video for live streaming
While experimenting with H.264 encoding, I came across some questions regarding certain configurations:
When I enable kVTVideoEncoderSpecification_EnableLowLatencyRateControl, is it still possible to use kVTCompressionPropertyKey_VariableBitRate? In my tests, I get an error.
It also seems that kVTVideoEncoderSpecification_EnableLowLatencyRateControl cannot be used together with kVTCompressionPropertyKey_ConstantBitRate when encoding H264. Is that expected?
When using kVTCompressionPropertyKey_ConstantBitRate with kVTCompressionPropertyKey_MaxKeyFrameInterval set to 2, the encoder outputs only keyframes, and the frame size keeps increasing, which doesn’t seem like the intended behavior.
Regarding the following code from the sample:
let byteLimit = (Double(bitrate) / 8) * 1.5 as CFNumber
let secLimit = Double(1.0) as CFNumber
let limitsArray = [ byteLimit, secLimit ] as CFArray // Each 1 second limit byte as bitrate
err = VTSessionSetProperty(session, key: kVTCompressionPropertyKey_DataRateLimits, value: limitsArray)
This DataRateLimits setting doesn’t seem to have any effect in my tests. Whether I set it or not, the values remain unchanged.
Since the documentation on developer.apple.com/documentation
doesn’t clearly explain these cases, I’d like to ask if anyone has insights or recommendations about the proper usage of these settings.
Thanks in advance!
The operation couldn’t be completed. (CoreMediaErrorDomain error -19156 - The operation couldn’t be completed. (CoreMediaErrorDomain error -19156.
Hello, We have Video Stream app. It has HLS VOD Content. We supply 1080p, 4K Contents to users. Users were watching 1080p content before tvOS 26. Users can not watch 1080p content anymore when they update to tvOS 26. We have not changed anything at HLS playlist side and application version. This problem only occurs on Apple TV 4th Gen (A1625) tvOS 26 version. There is no problem with newer Apple TV devices. Would you help to resolve problem? Thanks in advance
Topic:
Media Technologies
SubTopic:
Streaming
Tags:
FairPlay Streaming
Apple TV
tvOS
HTTP Live Streaming
Hello Apple team and developer community,
I am preparing a visionOS app for a fair environment, where we want to automatically stream the current experience to a nearby monitor via AirPlay, without requiring guests or staff to manually interact with the Control Center or AirPlay pickers all the time.
The goal is to provide a smooth, frictionless setup so attendees can focus on the demo, not the configuration.
Feature Request:
A supported API or method to programmatically start/stop AirPlay video streaming (mirroring or external playback) from within a visionOS app, allowing the current experience to be instantly displayed on an external monitor or Apple TV for the audience.
Context & Rationale:
In a trade fair or exhibition setting, rapid guest turnaround and minimal staff intervention are crucial. Having to manually guide each visitor through AirPlay setup is impractical.
As I understood, AVRoutePickerView can be used for this on iOS/macOS, but this is not available in visionOS. Enabling similar automated streaming on visionOS would make the device far more suitable for live demos and public showcases.
Questions:
Are there any supported workarounds or best practices for enabling automated screen streaming or AirPlay initiation on visionOS in public demo environments that I missed?
Is Apple considering adding programmatic AirPlay control or accessibility features to support such use cases in future visionOS releases?
Thank you for considering this request! If there are recommended patterns, entitlements, or accessibility solutions we could explore for trade fair scenarios, your guidance would be greatly appreciated.
Best regards,
Julian Zürn - IPI, HS Kempten
quotes are displayed incorrectly in subtitles of AVPlayerViewController when streaming VOD content using HLS.
single quote ' (escaped ') is displayed as apos;
double quotes " (escaped ") is displayed as quot;
following the vtt specification.
The same stream works fine in VLC player, showing quotes correctly in subtitles.
subtitle vtt files use
Content-Type: text/vtt
WEBVTT
X-TIMESTAMP-MAP=LOCAL:490014:06:04.000,MPEGTS:158764568760056
example line:
490014:05:46.000 --> 490014:05:50.440 align:start line:83% position:14%
and the playlist has:
#EXT-X-MEDIA:TYPE=SUBTITLES,GROUP-ID="subs",LANGUAGE="da",NAME="Dansk",AUTOSELECT=YES,CHARACTERISTICS="public.accessibility.transcribes-spoken-dialog,public.accessibility.describes-music-and-sound",URI="subs/dan_5/playlist.m3u8
#EXT-X-STREAM-INF:BANDWIDTH=780000,CODECS="mp4a.40.5,avc1.42c01e",RESOLUTION=256x144,AUDIO="audio-aac",SUBTITLES="subs"
lære dig endnu bedre at kende."
adding 'wvtt' to CODECS list in playlist does not make a difference.
Is this a known bug? Is there a workaround?
I guess the AVResourceLoaderDelegate can be used to intercept and parse the subtitle files, but it seems like quite a hack and not really intended to be used for this.
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.
Can some one please answer me How Can I update the cookies of the previously set m3u8 video in AVPlayer without creating the new AVURLAsset and replacing the AVPlayer current Item with it
ApplicationMusicPlayer with queue created from playlist crashes with random occurrence shortly after skipping back or forth using controls embedded in the notification, with the error on console log: applicationController: xpc service connection interrupted.
I've noticed that the issue occurs more frequently the shorter is time between skipping entries. Since ApplicationMusicPlayer is run on a remote process, the main app does not crash, but the music stops playing without any exception, and the playback control turns uninitiated.
Here is how I'm initiating the queue:
let entries = playlist
.with(.entries).entries!
.map { ApplicationMusicPlayer.Queue.Entry($0) }
ApplicationMusicPlayer.shared.queue = .init(
entries, startingAt: entries.last
)
Please give me some tips on how to solve this.
EDIT:
The issue does not occur when navigating quickly through the station.
In our Apple TV application, we are using the native AVPlayer for live playback functionality. During live restart playback, we intermittently encounter an error when the playback timeline approaches the actual live event end time.
Error:
The operation couldn’t be completed. (CoreMediaErrorDomain error -16839 - Unable to get playlist before long download timer) / Failure reason:
Scenario:
The live event is scheduled from 7:00 AM to 8:00 AM.
Restart playback begins at 7:20 AM, allowing the user to watch the event from the start while the live stream continues in real-time.
As the restart playback timeline approaches the actual event end time (8:00 AM), AVPlayer displays an error, and playback continues in the background.
Topic:
Media Technologies
SubTopic:
Streaming
Tags:
FairPlay Streaming
Media Player
HTTP Live Streaming
Hi folks,
When doing HLS v6 live streaming with fmp4 chunks we noticed that when the encoder timestamps slightly drift and a #EXT-X-DISCONTINUITY tag is created in either the audio or video playlist (in an ABR setup), the tag is not correctly handled by the player leading to a broken playback containing black screen or no audio (depending on which playlist the tag is printed in).
We noticed that this is often true when the number of tags is odd between the playlists (eg. the audio playlist contains 1 tag and the video contains 2 tags will result in a black screen with audio).
By using the same "broken" source but using Shaka player instead won't break the playback at all.
Are there any possible fix (or upcoming) for AV Player?
I can't play video content with HEVC and DRM. Tested HEVC only: OK. Tested DRM+AVC: Ok.
Tested 2 players (Clappr/Stevie and BitMovin)
Master, variants and EXT-X-MAPs are downloaded Ok, DRM keys Ok and then, for instance with BitMovin Player:
[BMP] [Player] [Error] Event: SourceError, Data: {"code":2001,"data":{"message":"The operation couldn’t be completed. (CoreMediaErrorDomain error -12927.)","code":-12927},"message":"Source Error. The operation couldn’t be completed. (CoreMediaErrorDomain error -12927.)","timestamp":1740320663.4505711,"type":"onSourceError"} code: 2001 [Data code: -12927, message: The operation couldn’t be completed. (CoreMediaErrorDomain error -12927.), underlying error: Error Domain=CoreMediaErrorDomain Code=-12927 "(null)"]
4k-master.m3u8.txt
4k.m3u8.txt
4k-audio.m3u8.txt
Hello All,
I am looking for assistance with our FairPlay Streaming (FPS) certificates. We are in the process of migrating to a new video streaming vendor and need to create a new FPS certificate using SDK 4. However, we have reached the limit of allowed FPS certificates in our account and cannot create a new one.
Issue Details:
• We currently have two FPS certificates active in our developer account.
• One of these was created using SDK 5, but our new vendor (Mux) requires an FPS certificate based on SDK 4.
• Since Apple does not allow deleting FPS certificates from the developer portal, we are unable to create a new SDK 4 certificate.
• We kindly request Apple to revoke one of our existing FPS certificates to allow us to generate a new SDK 4 certificate.
Request:
We would greatly appreciate it if you could assist us on how to delete one of our existing FPS certificates so that we can proceed with creating a new SDK 4 certificate for our vendor integration.
Thank you for your support.
Hello,
I am developing a video streaming service that uses FairPlay. Since around February 20th, we have started receiving reports of CoreMediaErrorDomain -42709 errors.
Unfortunately, there is no documentation from Apple that explains what this error means, so we are not sure how to address or fix the issue.
Most of the users who reported this error are using iOS 18.2.1 and iOS 18.3.1.
Could you please advise on what we should check or how we might resolve this error?
A few months ago, I had the opportunity to receive a 2018 iMac, and I’ve been using it to create content for my social media. I was truly impressed by the power of its processors. Even with this older model, I’ve been able to grow my presence online—something I couldn’t achieve with newer computers from other brands that I previously purchased.
I would love to become a promoter of your brand in the gaming world. All I ask for is technological support with more recent equipment and a minimal payment for collaborating with you. I am genuinely interested in being part of your company and leveraging the potential and reputation of Apple to reach even greater heights.
Topic:
Media Technologies
SubTopic:
Streaming
Tags:
GameplayKit
External Graphics Processors
Developer Tools
I have an iOS app that downloads HLS files, which are protected by FairPlay. These files are stored locally, and their locations are managed using Core Data. When playing these tracks, I use AVURLAsset to access the stored file paths.
Recently, a client upgraded to a new iPhone and used Quick Start to transfer data from his old device. While all other app data was successfully transferred, including Core Data records and UserDefaults, the actual HLS files were missing. As a result, the app retained metadata about the downloaded content, but the files themselves were gone, causing playback failures.
Does Quick Start exclude certain types of locally stored files, especially DRM-protected HLS downloads, or is the issue related to how FairPlay-protected content is handled during the transfer of locally stored files?
Topic:
Media Technologies
SubTopic:
Streaming
Tags:
FairPlay Streaming
Cloud and Local Storage
HTTP Live Streaming
AVFoundation
Hello, hope everybody is doing well. I have some reels (of aspect ratio 9X16) content, which I want to playback on iOS phones.
My question is does AV player support out of box playback of encrypted Mp4. Please note, this is not HLS fMp4, rather unfragmented Mp4 content.
If it is supported, what algorithm of encryption shall be used? Please let me know.
Topic:
Media Technologies
SubTopic:
Streaming