Channel guide rolls... On its own

Has anyone ever had the TV listing guide speed scroll on its own. I know if you hold the button down it will take off but with one touch of the up/down and it goes speeding through the channels. This also happens in the settings menus and DVR menus. I thought it was the remote first, got a different one, same thing. Then I thought it might be my 8642 top set due to we have been having problems. So... I replaced everything at the solution store. It is still doing it. I tried moving the box to higher spot, lower spot etc... still happening. Any kind of help would be helpful. Note: The guy at the Store said it was the remote. (wrong) Also this has worked fine where it was for the last 6 months.