So I spent an inordinate amount of time running coax from my basement up through a couple floors to my 2nd floor bedroom. What a pita. Now the display flickers like crazy, to the point where it's unwatchable. Every 3-5 seconds, it flickers. I would estimate the run was about 50', up the side of the chimney. It may or may not pass near some power cables in the basement. Is there any way to boost the signal or anything? I don't really want to have to run the line again if I can help it. Similar thing is also happening to the HD channels on my rear proj hdtv in the living room. This run doesn't seem to be near any power cables, but the HD channels seem to be having a tough time "keeping up" with sports and such. Never had a problem until we moved the TV to the other side of the room and used a different run. Is it possible this is something Comcast would fix from the outside?