CloudKit won't play CKAsset Song Swift 3

Question

I have a song stored in CloudKit as a CKAsset. I successfully retrieve the song and get no error but it just won't play. Any help would be appreciated, thanks.

My AVPlayer is lazily instantiated within the class.

//Create song player to play song, lazily instantiated
lazy var songPlayer: AVPlayer = {
    let player = AVPlayer()
    return player
}()

func playPause() {

    //Unwrap song - if there is no song, then return...you can't play something that is not there.
    guard let song = selectedArtist.song else {
        return
    }

    //Create player item
    let playerItem = AVPlayerItem(url: song.fileURL)

    //Add observer so app knows when the song reached its end
    NotificationCenter.default.addObserver(
        self,
        selector: #selector(itemDidFinishPlaying(notification:)),
        name: NSNotification.Name.AVPlayerItemDidPlayToEndTime,
        object: playerItem)

    //Assign playerItem to AVPlayer
    songPlayer = AVPlayer(playerItem: playerItem)

    if isSongPlaying {
        print("Song at \(song.fileURL) stopped.")
        isSongPlaying = false;
        songPlayer.pause()
        songPlayPauseImageView.image = UIImage(named: "play.png")
    } else {
        print("Song at \(song.fileURL) started.")
        isSongPlaying = true;
        songPlayer.play()
        songPlayPauseImageView.image = UIImage(named: "pause.png")
    }
}

When I start playing the song I get the message (as expected):

Song at file:///private/var/mobile/Containers/Data/Application/E34BE227-86DD-4AD7-A3C1-6A0610CE8C39/Library/Caches/CloudKit/6e22c352bc4bdeb0b75d42a0d681d67c69eeaad4/Assets/6BD84822-D039-4228-A5E9-59CB281BB964.0182fa97976e7d7b941bb8d8790ea75c6d3b72c302 started.

Unfortunately, the song doesn't play.