I'm having problems using my microsoft broadband networking router, model mn-700, and am hoping for some suggestions. I was previously using an RCA DCM425 modem with the router, no problems until the modem stopped working. I then switched to a RCA DCM425C, and the router no longer worked. The modem works fine when I plug the mac (running OSX 10.5.5) into the new modem, but once that router comes between them, the IP address changes and I can't connect. Any assistance would be greatly appreciated. Our ISP is comcast.