A switch may help resolve the issue. Recently tried a gateway router/modem from them and gave it back. Poor software, limited consumer controls, and their using my power to provide services to others without compensation. Too many other things that Comcast doesn't seem to refute or admit about them IMO; http://forums.comcast.com/
. When I first heard about their plan to piggy back Wi-Fi off of their customers backs I wanted to know how much they would pay me for an access point.
If you think the gateway is an issue you have to contact them and have them turn it off.