Thanks Corey. My Kamailio server is running on a VPS on internet with a public ip fixed (dedicated ip). I am using latest 4.2.1 kamailio on it with RTP proxy. Strange is that it works inside my house with wifi the 2 devices and works perfect audio, but with external devices on internet seems a problem. Any help on configurating and revise my server is appreciate as probably i am missing something to enable NAT config. If any kamailio expert is interested in contacting me for fixing this, we arrange the cost. regards, javier Date: Mon, 29 Dec 2014 17:42:20 -0700 From: tensai(a)zmonkey.org To: sr-users(a)lists.sip-router.org Subject: Re: [SR-Users] kamailio configuration problem On Mon, Dec 29, 2014 at 5:03 PM, javier falbo <javier_falbo(a)hotmail.com> wrote: Hi, I would like some help from a kamailio expert. I have installed on a Debian7 64 kbytes VPS this tutorial: http://kb.asipto.com/kamailio:skype-like-service-in-less-than-one-hour, Problem is that there is no voice in a zrtp connection, but i hear only the ring sound ok. Strange is that on my local wifi works all perfect including the voice, but with external ip no. Any help? I would like to hire a kamailio expert for fixing this and also adding some extras. Write me directly so we could get in contact. Kamailio itself doesn't handle media, only SIP. Your issue sounds disturbingly like a NAT problem, which is not uncommon. Are you using the nathelper module? Are you using an RTP relay such as RTP Proxy or MediaProxy? Is your Kamailio server behind a NAT? Please provide SIP traces, logs and configs and we'll do our best to assist. Corey _______________________________________________ SIP Express Router (SER) and Kamailio (OpenSER) - sr-users mailing list sr-users(a)lists.sip-router.org http://lists.sip-router.org/cgi-bin/mailman/listinfo/sr-users