Dear Gurus,

We have a user behind NAT.
Currently we make him work by using
      <variable name="sip-force-contact" value="sip:1234@171.134.62.106:5060"/>
It works since users IP is static and there is a port forwarding setup for port 5060 on the users side.

The problem is that after 15 minutes of a call FreeSWITCH attempts re-INVITE (RFC 4028 I guess) and does not honour port specified above.
Instead, it uses some 40,000-ish UDP destination port.  Obviously, this never reaches users phone and FS hangups with "expiry on timer" cause.

Is the syntax of sip-force-contact above valid?

Is it normal for re-INVITEs no to honour sip-force-contact?

I'd try NDLB-tls-connectile-dysfunction but I need clarification:
-will it be honoured by re-INVITEs?
-will it default to port 5060 or should I specify the port?

Thank you,
Victor