title: MPNowPlayingInfoCenter nowPlayingInfo ignored for AVPlayer audio via AirPlay
body: <p>I have implemented audio playback using AVPlayer, playing a remote mp3 url.</p>
  
  <p>I want to display the information about the currently playing audio using the <code>MPNowPlayingInfoCenter</code> <code>nowPlayingInfo</code> method.</p>
  
  <p>When I lock the screen, I do see the image and title I set, so I know that this method is registering the information in some way, but when I switch to AirPlay to an AppleTV, the display looks like a generic video output, with the progress bar at bottom, but elapsed time and duration correctly displayed.</p>
  
  <p>If I set this same <code>nowPlayingInfo</code>, but then start some audio using an AudioQueue, then it properly displays the image on half the screen (it looks just like playing a podcast with the iPod/Music app).</p>
  
  <p>Is this just a limitation of AirPlay support for audio using AVPlayer, or is there some way to get it to display the image and info properly?</p>