No, I don&#39;t use Xlite. I use my own .Net wrapper around pjsip ua lib. Foreseeing uncertaincies about it&#39;s quality I may say that pjsua reference implementation yields the same results in this scenario. <br>Actually I have no doubt that FS is working nicely with tcp and tls as well because I had it working till some moment. And I don&#39;t know what the hell happened. =(<br>

In order to check if it is something related to my config I switched it back to default and conducted the same test with (urghhh) no luck as well. <br>So now I wonder what could cause this very-very strange behavior? Some issues with network? But why the UDP works then?<br>
<br>All traces (FS SIP, FS console, SIP caller and callee&#39;s) are here: <a href="http://pastebin.com/m2008de4e">http://pastebin.com/m2008de4e</a><br><br>Regards, Robert.<br>