"johnelstad" wrote ...
Pooh Bear: At first I thought I hadn't moved anything, but now I
realize that two weeks ago I signed up for cable to watch the World
Cup. I now have a splitter that goes to my cable modem and directly to
my tv. Disconnecting the coax cable from my tv kills the hum.

Any suggestions? Thanks again!

That is a very common problem. The cable system uses a different
ground reference than your power/mains system uses. There is
always some voltage difference between these grounds. This is what
you hear as "hum". In some cases the difference has been reported in
the mid-50 volt range(!)

Several vendors make isolation transformers for the cable connection.
Highly recommend that solution in preference to any others.