title: Firefox crashes when a websocket call answered
body: <p><br>
  I'm experimenting with asterisk 13 and sipml5 on a cantos virtual machine, Everything is configured properly.
  <br> 
  I use Firefox 38.0.1 to make calls from an extension to the other, and till last night everything worked just fine.
  <br>
  Now today when I start to call an extension and want to answer that call, firefox suddenly crashes.
  Any help will be highly appreciated.</p>