Garbled picture

[ObiWanJenkins]

Having just gotten an 80 hour Tivo for my living room, I tried to move my 40 hour upstairs to one of the bedroom TV's. It seems that my 40 hour Tivo will not display anything but a garbled picture when using coxial cable or the RCA inputs. I tried it on two TV's, one a Toshiba with s-video and component. The other is a generic TV/VCR model with only a coxial and mono video input. The RCA and coxial connections are garbled on both TV's, but the s-video on the Toshiba looks great. I've changed the settings on my Tivo to reflect the change to non s-video output, restarted the machine, and hooked it up three different ways. Does anybody have an idea how to make this work or am I simply boned?

[ObiWanJenkins]

This doesn't appear to be a weak signal, as the vertical and horizonal syncs seem to be off, but there's no snow or other interference. Could the tuner be bad since I've only been using the s-video output for the last two years?