We had that problem for a while right after we first got cable modem service, John. It turned out that the problem was the cable linking the house to the street. The cable service weenies couldn't figure that out... it was their TV guy, who snapped to the problem when we told him that the low # TV channels were having problems too. Replaced the cable and no more problems since. I'm completely empathetic, I know what a major pain in the rear the 0Kb/hr service from those guys can be like!