NO JOY Occasional loss of registration with VoIP.ms using GXV3240

[Tom Clark]

We installed a Grandstream GXV3240 in my wife's office a couple of weeks ago, and it worked right out of the box, but a few days later it lost registration to the VoIP.ms server for a few hours. Rebooting the phone solves the problem, as does waiting for a few hours for it to re-register. I talked with VoIP.ms tech support, and they had me change the SIP Port Number, but the problem reappeared a few days later. When I contacted them again, they suggested that it might be related to SIP ALG or SPI Firewall settings and suggested that I disable them. Unfortunately, I am not affiliated with the tech support people at her office, so asking them to disable settings on their firewall is out of the question. VoIP.ms also suggested changing the SIP transport from UDP to TCP. Does this sound like a viable solution? If so, I'll have my wife change the configuration once she gets into the office. Also, since the GXV3240 has VPN capability, would routing the phone through a VPN provider bypass the ALG and SPI settings that VoIP.ms was talking about?