I know this is an old thread but thought I would ask a question here anyway. I scanned thru most of this thread but didn't find any reference to my problem.
On HDMI input, after the TV has been on a while, I get horizontal streaks across the screen. Not bad, just enough to be annoying. If I shut the TV off, the problem is gone when I restart. Or, if I switch to AV input then back to HDMI, the problem is gone for a while then comes back after 25-30 minutes.
Any ideas? I am not an electronics guy, but I would guess it is acting like a static build up of some sort since the problem goes away by switching inputs or power cycling the TV.
I have had my Visio GV42L for about 4 years now with no other issues at all and it gets used a lot.