If the TV was still snowy...and the Tivo was disconnected...it cannot produce a Snow related signal on the TV set.
Snow isn't a LACK of signal..it's just Noise with no rhythm or consistent pattern or constancy like a picture is. It's a source of signal. That's why I asked if you disconnected or remove the Tivo, was the noise still present?
Same with the TV's Menu...you either see it or you don't. And does the noise appear ON or behind the menu....that tells you whether the noise source occurs BEFORE or AFTER the menu signal is created or laid on the entire layer of video.
I ask these questions because they ISOLATE the problem
That's also why I'm interested in other equipment connected to your TV set.
Let's not center in on what the Tivo does or what you did to it.
Center in on the TV menu.
Center in on some other source of picture to your TV set.
You unplug the Tivo....and you still get snow.
It's not the Tivo then.
Let's move on to other tests to verify.
Menu? Is there still snow when the menu is activated?
Is the snow only behind the menu? Or does the snow look like its ON the menu?
You don't have anything else in your household like a DVD player?
No Cable or Satellite?
Not even a local antenna to pick up local TV stations??
Not even a long piece of wire that plugs into the center hole of your antenna connector and strung halfway up the wall? Any Digital TV tuner can get SOME channels unless you're in the middle of nowhere.
Tivo can't be your only source of enjoyment, is it?