it could be 2 things, one being your router is at the end of its life. Or you have too many splitters on your cable line going to your router. once that happened to us and a Comcast guy came out and removed 2 unnecessary splitters and our internet worked again! after that we had the 2.4 GHz Comcast router with 105 Mbps and when they upgraded us to 150 Mbps for free the old 2.4 router wouldn't even get to that speed. so i called Comcast and told them i wanted the new gateway 3 router (dual band router) and they said ok and set out a tech to install the new router. there is not a tech fee because it is a service call. if Comcast tells you there is a fee with the new router, hang up and call again to get a different person. there is no fee for upgrading a router because its trading old equipment in for new equipment. SOLUTION: call Comcast and tell them you want the new gateway 3 router