CMD31T talks to everything but Wireless Router

[Adycs]

My CMD31T is feeding internet fine when plugged directly in to a PC or Xbox but in any wirless router, I am able to connect to the router but there is not internet. Comcast is our ISP and we have tried a Linksys WRT120N, Linksys WRT54G, and a brand new TP Link TL-WR940N out of the box. This happened suddenly, any thoughts?

[plemans]

when you're setting up, are you doing it in this order? 

power off both modem and router and disconnect devices from both. 

connect modem to coax and power on. give it several minutes to fully boot. 

connect ethernet from modem to router wan port. Then power on router. give it a few minutes to boot.

Try to do setup...