I'm just wondering if people have further feedback about the Debian SIP service https://rtc.debian.org has just been updated to overcome some issues with local audio feedback For Firefox/Iceweasel users, there have been fixes in both the JSCommunicator code and the Asterisk instance behind http://www.sip5060.net/test-calls so this should also be stable. If there are complaints that haven't been answered, please let me know.