title: AudioCodecs in Android Native Sip stack
body: <p>Code from android.net.sip.SipAudioCall:  </p>
  
  <pre><code>  for (AudioCodec codec : AudioCodec.getCodecs()) {
                  media.setRtpPayload(codec.type, codec.rtpmap, codec.fmtp);
              }
  </code></pre>
  
  <p>Does it mean that native android sip stack uses not only g711(pcmu/a), but also GSM?</p>
  
  <p>If "Yes" - can I set not all codecs, only those that I want?</p>