There are MANY variables that can cause your problem. By eliminating some of these variables, you could track down the cause. First and foremost what I would do is take the router out of the equation. Plug the ATA directly to the gateway. Make the phone calls for a while and see if the problem still exists. If not, it could be something with the router OR something on the network as a whole causing the problem. If it DOES still exist, it could be the gateway device itself. Some gateways have their own firewalls/port forwarders, etc. that need tweeking. Many people don't think to check this. *IF* that's not the problem, then yes, there very well could be an issue between your home to wherever on the internet VOIPo's servers are located. They can re-program you to different locations. This may or may not fix the issue. But at least these steps would be a good start.