title: asterisk early media audio issue
body: <p>I didn't get any audio in sip calling when using early media feature of asterisk.</p>
  
  <p>Normally its working fine but due to playback apps, asterisk answer the sip channel and timer of user start that should not be happen.
  That why I am trying to implement early media option in asterisk.
  It is working as said but problem occur in audio. I could not hear anything unless user pick the phone.</p>
  
  <p>extension.conf</p>
  
  <p>exten => _X.,1,Progress()</p>
  
  <p>exten => _X.,n,Playback(/var/lib/asterisk/sounds/verification,noanswer)</p>
  
  <p>exten => _X.,n,Dial(SIP/channel/number)</p>
  
  <p>sip.conf</p>
  
  <p>[xxx]</p>
  
  <p>fullname=xxx</p>
  
  <p>type=friend</p>
  
  <p>host=dynamic</p>
  
  <p>disallow=all</p>
  
  <p>allow=g729</p>
  
  <p>allow=ulaw</p>
  
  <p>allow=alaw</p>
  
  <p>allow=gsm</p>
  
  <p>username=xxx</p>
  
  <p>secret=xxx</p>
  
  <p>context=sip-calling-test</p>
  
  <p>qualify=yes</p>
  
  <p>call-limit=2</p>
  
  <p>nat=yes</p>
  
  <p>Does any one know what is the problem.</p>