Issues when previewing .flac files with AVPlayerViewController

Question

I am using AVPlayerViewController to preview all formats of audio in my app.
Everything was working fine but after I added support for .flac files, it became buggy.

Sometimes the player loads the video correctly, and sometimes does not. This never happens for other formats, for example .mp3 .

This is how it looks like when video is loaded correctly and when it is not (first image is when everything is fine):

The logic is the same for all audio formats:

private lazy var _player = AVPlayer()
private lazy var _playerViewController = AVPlayerViewController()

func playAudio(correctUrl: URL) {
    var item = AVPlayerItem(url: correctUrl)
    self._player.replaceCurrentItem(with: item)
    self._playerViewController.player = self._player
    self.registerForAVPlayerNotifications()
    self._playerViewController.player?.play()
}

Answer 1

Try loading asset as AVURLAsset and check the possible loading error.

func loadAsset(_ streamUrl: URL,completionAfterLoad: ((AVPlayerItem) -> Void)? = nil) {
    let asset = AVURLAsset(url: streamUrl, options: nil)
    let assetKeys = [
        "playable",
        "tracks",
        "duration"
    ]
    // Create a new AVPlayerItem with the asset and an
    // array of asset keys to be automatically loaded
    
    asset.loadValuesAsynchronously(forKeys: assetKeys, completionHandler: {
        
        DispatchQueue.main.async {
                var error: NSError? = nil
                var status = asset.statusOfValue(forKey: "playable", error: &error)
                switch status {
                case .loaded:
                    print("loaded\n\(String(describing: error?.localizedDescription))")
                case .failed:
                    print("failed\n\(String(describing: error?.localizedDescription))")
                case .cancelled:
                    print("cancelled\n\(String(describing: error?.localizedDescription))")
                default:
                    print("default\n\(String(describing: error?.localizedDescription))")
                }
                
                status = asset.statusOfValue(forKey: "tracks", error: &error)
                switch status {
                case .loaded:
                    print("loaded\n\(asset.tracks)")
                case .failed:
                    print("failed\n\(String(describing: error?.localizedDescription))")
                case .cancelled:
                    print("cancelled\n\(String(describing: error?.localizedDescription))")
                default:
                    print("default\n\(String(describing: error?.localizedDescription))")
                }
                // If loading of duration fails, stream plylist is in wrong format (e.g. missing version number etc.)
                status = asset.statusOfValue(forKey: "duration", error: &error)
                switch status {
                case .loaded:
                    print("loaded\n\(asset.tracks)")
                    
                case .failed:
                    print("failed\n\(String(describing: error?.localizedDescription))")
                    
                case .cancelled:
                    print("cancelled\n\(String(describing: error?.localizedDescription))")
                default:
                    print("default\n\(String(describing: error?.localizedDescription))")
                }
                
                print("tracks\n\(asset.tracks(withMediaType: .audio))")
                
                let playerItem = AVPlayerItem(asset: asset, automaticallyLoadedAssetKeys: assetKeys)
                completionAfterLoad?(playerItem) // perform any action to happen after playlist is completed loading
        }
    })
}

// Usage:
let avPLayer = AVPlayer()
let url = URL(string: "")!
loadAsset(url,completionAfterLoad: { playerItem in
  avPLayer.replaceCurrentItem(with: playerItem)
})