I have a field office with Comcast service. The device is the Netgear CG814CCR. We have a static IP defined to this device. We are using vonage for our phone service. The problem is that the device tends to cause problems if we use any other routing device behind it. Our goal is to hook up a SonicWall TZ-170W behind the device and establish a VPN tunnel to our main office's PRO2040 device. The tunnel establishes fine and works for awhile, then the two networks quit talking to each other (pings fail). We thought we may have a SonicWall issue, but removed the device from the topography totally (using the built in router on the Vonage). We then connected a PC using the SonicWall Global VPN client and the same connectivity issues reappeared. The only way we can get any stability at all is to connect our PC's/phones directly into the CG814CCR. We still have some voice issues occasionally, but it is much more stable. Since the symptoms occur without the firewall in place, I'm confident that isn't the issue. Comcast says they can't see any problems, and have been mostly unresponsive in helping diagnose the problem. Presently, we have our PC's/printers plugged directly into the CG814CCR, getting IP addresses from the device. We have another field office using a TZ170 using a tunnel and it works perfectly. I reallly thinik the problem is within the CG814CCR device, but am having difficulty getting anybody at Comcast to believe me. They swear that the built in firewall is turned off, but I have my doubts. Ideally, we only need that device for the Static IP and we can handle everything else with our SonicWall. Am i missing something here or am I right in pursuing this with Comcast? I'm really at a loss into how to proceed. This isn't a complicated setup at all. Any advice or suggestions would be appreciated.