MPNowPlayingInfoCenter error

With tvOS 10 setting the nowPlayingInfo worked without error and it showed the new infos on the top right corner above the screen saver of tvOS.

With tvOS 11 i see this error in Xcode and no playing info is displayed on top of the screen saver:

2017-07-12 16:41:45.454945+0200 radio.net[277:19185] [Default] No LanguageDataSource for item <TVPMPNowPlayingContentItem: 0x1c44b4be0 id=8BAFBBD6-9A4E-466E-9D8D-4D93C02434A9 title="Born in the U.S.A. / Bruce Springsteen">

2017-07-12 16:41:45.457201+0200 radio.net[277:19185] [MediaRemote] Error Operation requires a client data source to have been registered. requesting item 8BAFBBD6-9A4E-466E-9D8D-4D93C02434A9 "Born in the U.S.A. / Bruce Springsteen" with <_MRPlaybackQueueRequestProtobuf: 0x1c4291490> {

includeLanguageOptions = 1;

length = 1;

location = 0;

requestID = "718E8BAC-0317-43B8-A93C-BB29601DDB29";

returnContentItemAssetsInUserCompletion = 1;

} at indexPath (

0

)

I guess i have to set the LanguageDataSource? I did not find out how to do this yet. Also, what does client data source mean?

What do i have to do to let the nowPlayingInfo appear for my app on tvOS 11?

The code is this:

func updateNowPlaying(title:String, artworkImageURL:String) {

    var currentlyPlayingTrackInfo: [String : Any]?

    var image:UIImage = UIImage(named: "radio.png")!
    let url = URL(string: artworkImageURL)
    let data = try? Data(contentsOf: url!)
    if (data != nil) {
        image = UIImage(data: data!)!
    }
    let artwork = MPMediaItemArtwork.init(boundsSize: image.size, requestHandler: { (size) -> UIImage in
        return image
    })


    currentlyPlayingTrackInfo = [MPMediaItemPropertyTitle: title,
                                MPMediaItemPropertyMediaType: MPNowPlayingInfoMediaType.audio.rawValue,
                                MPMediaItemPropertyArtwork: artwork]
    MPNowPlayingInfoCenter.default().nowPlayingInfo = currentlyPlayingTrackInfo
}

In Xcode debug output i can see this:
[MediaRemote] [NowPlayingInfo] Ignoring nowPlayingInfo update because playback queue callbacks are set