I'm not sure how to do that myself. I guess Comcast might have really needed to send a tech over to install the Voice device.
I just dialed *** and got a busy signal.
Oh, I just remembered how to login as admin to the gateway.
Here's a screen shot. Does this help?
As for setting up that port forwarding stuff, I have NO idea what I'm doing and don't want to risk winding up with no phone or internet?
Is this box a Grandstream?