I'm a VOIP Express customer forwarding my old home phone number to my PBX (Asterisk 1.6). When I use the beta SIP support in the forwarding settings of vPanel, I only can hear the callee's voice (from PBX to the caller) and the caller's voice (from caller through VOIPo to PBX) is missing.

All of my other VOIP providers are working fine with the PBX with voice working in both directions, so I doubt it is a firewall issue.

Any advice? Is anyone else successfully using the VOIP Express forwarding to a SIP account from an Asterisk 1.6 PBX, or even to another SIP BYOD device?

Thanks!