title: Android setStreamVolume to ZERO doesn't work in Android 4
body: <p>I noticed that under Android 4.x setting ring volume to 0 is not possible. If I execute this code and then I go to Settings--> Sound --> Volumes I can see it is set to 1. I</p>
  
  <pre><code>audiomanager.setStreamVolume(AudioManager.STREAM_RING, 0, 0);
  </code></pre>
  
  <p>Do you know why? 
  I know I could use audiomanager.setRingerMode(RINGER_MODE_SILENT) but annoys me!! because in this case I would have to "remember" if vibration is on or off for activating again sound.</p>
  
  <p>Of course, all this works in other Android versions.</p>