title: Can you have playback of both MPMusicPlayerController and AVAudioPlayer over AirPlay?
body: <p>My iOS app uses the <code>MPMusicPlayerController.applicationMusicPlayer</code> to play music and it can also play other sounds via AVAudioPlayer simultaneously.</p>
  <p>It works fine playing through either the device speakers or bluetooth earphones / headsets.</p>
  <p>When it comes to AirPlay to devices like Apple TV or HomePod, the music is sent but the AVAudioPlayer stuff remains on the device. I want everything over AirPlay!</p>
  <p>Note: the audio session is initialized like so:</p>
  <pre><code>try? AVAudioSession.sharedInstance().setCategory(.playback, mode: .default, options: [.allowAirPlay, .mixWithOthers])
  </code></pre>
  <p>I cannot use the <code>longForm</code> policy because that would stop the music. I've tried different things here but no luck so far.</p>