Hi, I'm trying to do some realtime audio processing on audio served from an HLS stream (i.e. an AVPlayer created using an M3U HTTP URL). And I find that new APIs(AVPlayerItemSampleBufferOutput) are available in iOS 27.0 to achieve it. However, I failed to get the available data via the AVPlayerItemSampleBufferOutputDelegate. And I found some error in the system log: I create AVPlayerItemSampleBufferOutput and set the delegate after receiving the AVPlayerItemStatusReadyToPlay event. And here's my code: @interface OCAudioSamplebuffer () <AVPlayerItemSampleBufferOutputDelegate> @property (nonatomic, strong) AVPlayerItemSampleBufferOutput *bufferOutput; @property (nonatomic, strong) dispatch_queue_t bufferOutputQueue; @property (nonatomic, strong) AVPlayerItem *playerItem; @end - (void)playItem:(AVPlayerItem *)item { if (@available(iOS 27, *)) { AVAudioSession *audioSession = [AVAudioSession sharedInstance]; if([NSThread mainThread]){ [audioSession setCategory:AVAudioSessionCategoryPlayback withOptions:AVAudioSessionCategoryPlayback error:nil]; [audioSession setActive:YES error:nil]; }else{ dispatch_async(dispatch_get_main_queue(), ^{ [audioSession setCategory:AVAudioSessionCategoryPlayback withOptions:AVAudioSessionCategoryPlayback error:nil]; [audioSession setActive:YES error:nil]; }); } AVPlayerItemSampleBufferOutputAudioConfiguration *cfg = [[AVPlayerItemSampleBufferOutputAudioConfiguration alloc] init]; CMFormatDescriptionRef formatDescription = [self createPCMFormatDescriptionWithSampleRate:44100.0 channels:2 isFloat:YES]; cfg.requestedAudioFormat = formatDescription; if (formatDescription) { NSLog(@"create PCM Format Description success"); CFRelease(formatDescription); } else { NSLog(@"fail to create PCM Format Description"); } self.bufferOutput = [[AVPlayerItemSampleBufferOutput alloc] initWithConfiguration:cfg]; NSLog(@"create buffer success, PCM Format Description%@---,%@", cfg.requestedAudioFormat, formatDescription); self.bufferOutputQueue = dispatch_queue_create("audioSamplebufferQueue", DISPATCH_QUEUE_CONCURRENT); [self.bufferOutput setDelegate:self queue:self.bufferOutputQueue]; [item addOutput:self.bufferOutput]; self.playerItem = item; } else { // Fallback on earlier versions } } Any help. Thank you