We just ported a branch from TDM to SIP.
The branch has an MGCP gateway with FXS ports and a FAX machine plugged into one of the ports.
Since the port, the branch is unable to receive FAXes from most local and LD transmissions, it worked before the port.
We have other branches using the SIP for FAXes with no problem, the CUBE router dial peers are configured for FAX passthrough and no VAD and are all configured the same.
Calling the FAX number results in the call getting routed to the branch gateway, the FXS port goes off hook and the FAX handshake begins.
You can hear the tone and it almost immidiately stops, but the call stays connected.
One user sent a FAX, it rang once and the report showed "no answer", but some FAXes get through.
Another user cannot send to the branch from home (rings once), but the branch can send to her home.
Any input would be appreciated.
