title: Play sound in background using AVAudioPlayer without stopping ipod music
body: <p>In my app at particular time i am alerting user with beep sound which i am  playing using <code>AVAudioPlayer</code>. </p>
  
  <p>Now i want this sound to be played even when app is in <strong>background</strong>. So i can achieve this by setting <code>AVAudioSession</code> category as <code>AVAudioSessionCategoryPlayback</code> and i also want that this sound should not stop the ipod music and i can do it with it setting <code>AVAudioPlayer</code> category <code>AVAudioSessionCategoryAmbient</code>.</p>
  
  <p>But i want them together means sound should also play in background and it should also not stop the ipod music. </p>
  
  <p>So how can i achieve this? </p>
  
  <p>If it is not possible to play sound with <code>AVAudioSessionCategoryAmbient</code> category in background then any other workaround this?</p>
  
  <p>Apologies if i am doing any mistake.</p>
  
  <p>Thanks.</p>