Switch to cable internet - now connection issues - any suggestions?
 

I just switched over from a DSL dry loop connection (static IP) to a rather faster cable connection (dynamic IP). So far, so good, except for one thing. The exact same VoIP setup I had which worked perfectly on DSL doesn't quite work on cable. More specifically, for each and every call, after 40-45 seconds in (during which the call goes fine - dials out, connects, I hear the voice), the call dies - no sound coming in, and no sound going out - just silence.

My configuration did not change other than swapping out the DSL modem for a cable modem. If it might be helpful to diagnose here is the connection path:

Teksavvy Cable
Motorola SB6120 Cable Modem
NETGEAR ProSafe VPN Firewall FVS338
NETGEAR JGS424F Switch
Sipura SPA-3000 ATA

The FVS338 is configured to use NAT. I'm using the ATA to connect to Voxalot, which in turn is linked up to a couple of service providers.

Any thoughts or suggestions, whether to resolve the issue or to try to diagnose, would be appreciated.

Sounds like a firewall related issue.
Try to put your ATA just after the Modem (ie on puplic IP address), and feed the rest of the network from the private ip address port on the ATA if that is available.

If the ATA is behind a firewall, probably STUN setup in the ATA is required.

STUNned
 

Thanks very much for the note. Yes, turns out I needed to configure STUN properly. Once I did that everything worked beautifully.