It sounds like the rogers modem needs to be configured slightly different. There be some conflicts with the modem lan and pfs wan setup. I'm gonna blame the modem. if you can log into the modem remember you just want it to talk to the internet for you and thats all. I know the newer rogers modems have a config page you can get to and tweak.
I have rogers too just not the wireless. I planing to switch back to DSL b/c it run the same 10mbps/80kbps as cable. (Look into Primus if you do want switch)