Hello, I'm very new to freeswitch and telephony in general. I've managed to register phones with my server, but when I place test calls, the phone hangs, even though fs_cli tells me that the call was completed successfully. Also, everything looks fine when I run sip trace. FWIW, I've tried both linphone on Linux and csipsimple on Android. All of this is taking place on my LAN, so NAT isn't an issue. I started looking at traffic with tcpdump, and here's what I found. The phone authenticates to FreeSwitch and initiates the call. FreeSwitch sends a "100 trying" SIP message, followed by a UDP packet containing what appears to be SDP. It has no SIP header. This is followed by RTP from FreeSwitch to the phone. There is never a "200 OK" SIP message. Next, I ran linphone in debugging mode. I'll include a link to the log, in the hope that it will be helpful. Apparently, linphone isn't parsing the packet after the 100 trying message. Any idea what is going on here? http://the-brannons.com/linphone.log -- Chris