I can't recall if that set had wi-fi or not. If it does, and is trying to update, maybe it's something associated with that?
On another note, you won't find a much better picture than that set had. The full array local dimming is excellent on that set, that's IF you could live with the blooming certain movies had. I couldn't, so I got rid of that, and the next years model as well, the ones that offered 3D.
That's one of the highest rated sets for that year from a lot of reviewers, and that accounts for all brands, not just Vizio. I do recall others having issues with turning on and off for a while, but after a while it had stopped and those of us in that thread chalked it up to an update being forced and not finishing correctly. Do a search on that model and you'll find the proper thread, and ask in there for assistance.