I have a strange problem on using jitsi SIP with a FritzBox. The connection to the FritzBox SIP server is made through a VPN application.
My local IP is 192.168.11.123, my local IP of the VPN tunnel is 220.127.116.11. The IP of the FritzBox is 18.104.22.168.
After entering the SIP account informations I can successfully register to the FritzBox SIP server. But when I start a call the SDP of the INVITE directs the RTP stream to 192.168.11.123 instead of 22.214.171.124. Of course the FritzBox does not know about 192.168.11.123 and so voice fails.
Is there a way to define the local IP jitsi should work with? Or is there another solution to that problem?
BTW: The VPN application is not creating a extra network interface. So 'ipconfig |find "126.96.36.199"' on a windows machine does not show anything.