title: Airplay of audio using AVPlayer does not work in the background
body: <p>I am doing audio playback using the AVPlayer class from a remote URL.</p>
  
  <p>It plays fine if I just play to the headphones/built in speaker, but I am seeing some oddities with AirPlay.</p>
  
  <p>When I change to use an AppleTV for AirPlay, it will stream the audio, but on my iphone the audio playback indicator (the small 'play' triangle in the top menu bar) disappears, and when I lock the phone instead of continuing in the background, it stops. (When playing normally, it plays in the background fine).</p>
  
  <p>Why is the AVPlayer not working in the background for audio over AirPlay?</p>
  
  <p>Is this what other see? Is there a way around it?</p>