title: Play sound in background without obeying iPhone ring / silent switch
body: <p>My app must be able <strong>to play alarm sound no matter what</strong> upon <strong>receiving push notification</strong>.</p>
  
  <p>Is there a way to configure audio session to play sound:</p>
  
  <ol>
  <li>and <strong>NOT obey silent switch</strong> (route may be respected)</li>
  <li><strong>upon arrival of push message</strong> (can be silent) and if app is in the background or <strong>even if killed by the iOS</strong> in the meantime ?</li>
  <li>Sound is played even if user uses any other audio app (unconditional mix).</li>
  </ol>
  
  <p>I do not need to publish this app to AppStore (only for my private usage), so <strong>private API is an option</strong>.</p>
  
  <p>For those who may tempt to propose <code>UILocalNotification</code>: those are not suitable in my case since they must obey silent / ring switch.</p>