title: Custom iOS push notification sound
body: <p>I have been facing an issue. I implemented push notification in iOS with custom sound. Its a MP3 file. It plays well when I receive a push notification in iOS 5, but in iOS4, it doesn't play any sound.
  Can you help me with this?</p>
  
  <p>The code is like this</p>
  
  <pre><code>{
      "aps": {
          "badge": 10,
          "alert": "Hello",
          "sound": "sound.mp3"
      }
  }
  </code></pre>
  
  <p>Nithin</p>