The main (and only problem?) is that the modem keeps restarting itself, and I'm unsure why. The wires are fine. If it's any reason, the modem gets/is really hot when it's working. The coaxial cable even hotter, there is a open fan in the room the modem's in. As well, my NAT Type 2 is moderate rather than 'open'.
I had a rental SMCD3GN router that was rebooting all the time. The only thing that seemed to work was a replacement modem and power supply. If you are renting, pop into a Rogers Plus store for that. If not, hopefully your modem is still under warranty.
The power supply I had when it was rebooting itself was a two piece: a 120 volt two prong AC plug connected into a separate DC power pack. The new one I have is in one piece, the power pack plugs directly into the wall. That said, I'm not sure if it was the modem or the power supply that was defective, however a Rogers Plus store will give you both in a new plastic bagged 'bundle' package.