MPRemoteCommandCenter not working with MPMusicPlayerController applicationMusicPlayer

Hey guys,

I'm working on an App that plays Apple Music tracks. Therefore I'm using

MPMusicPlayerController.applicationMusicPlayer

everything is working great so far - including setting the

musicPlayer.currentPlaybackRate

which is kind of important for my use case.

Now I'm trying to setup of the lock screen-controls for my App correctly, especially because using the default ones will reset the currentPlaybackRate to 1.0 after play/pausing. Also I have to sync my internal playState if "pause" is pressed in the lock screen.

Here is what I wrote:

class AudioPlayerViewModel {
...
    private let commandCenter = MPRemoteCommandCenter.shared()
    init(album: LibraryAlbum? = nil) {
        ...
        self.setupRemoteCommandCenter()

    }

...
func setupRemoteCommandCenter() {
        debugPrint("setupRemoteCommandCenter()")
        
        commandCenter.previousTrackCommand.isEnabled = false
        commandCenter.previousTrackCommand.addTarget { event in
            debugPrint("remote previousTrackCommand")
            self.previousTrack()
            return .success

        }

        commandCenter.nextTrackCommand.isEnabled = false
        commandCenter.nextTrackCommand.addTarget { event in
            debugPrint("remote nextTrackCommand")
            self.nextTrack()
            return .success
        }

        commandCenter.pauseCommand.isEnabled = false
        commandCenter.pauseCommand.addTarget { event in
            debugPrint("remote pauseCommand")
            self.isPlaying = false
            self.pausePlayback()
            return .success
        }

        commandCenter.playCommand.isEnabled = false
        commandCenter.playCommand.addTarget { (event) -> MPRemoteCommandHandlerStatus in
            debugPrint("remote playCommand")
            self.isPlaying = true
            self.continuePlayback()
            return .success
        }
    }
}

I call setupRemoteCommandCenter() once(!) before playing anything in MPMusicPlayerController.applicationMusicPlayer

My problem is these handlers never get called. The lock screen-controls always remain the default ones. My code has no effect, but also throws no errors.

I find several posts about this. The Apple Documentation (https://developer.apple.com/documentation/mediaplayer/handling_external_player_events_notifications) states the this should be possible.

What am I doing wrong?

Any help would be greatly appreciated.