I have a Westinghouse W2613 LCD TV that I bought four years ago.
About 6 months ago, I turned the TV on & the intro screen that displays the Westinghouse logo was distorted. I cycled the power & the picture returned to normal.
What started as an occasional glitch has now become an everyday problem. This morning I had to turn the TV on & off about a dozen times before the video stabilized.
I have a VCR, DVD player, antenna, & HDMI from my computer connected to the TV. When the problem occurs, it affects all inputs.
It’s really strange. Once I get the TV to turn on correctly, the picture remains sharp for as long as the TV is on. The problem only occurs on start up.
The distortion varies. Sometimes it’s like a jittery over-scan. Sometimes it appears to be rolling. Sometimes it looks like several broken bands.
The most common cause of problems in devices like this today are “bad caps”. Especially the capacitors in the power supply, which could be causing your problems based on your symptoms. (I’ve seen several devices, including LCD displays, which don’t power up right the first time but eventually do. All caused by bad caps. The caps sometimes work a little better after they are warmed up.)
The visible symptom of most bad electrolytic caps is a bulging top and perhaps some leakage around the base. (Not the same as the gunk they put on there to keep them from rattling around.)
You can unplug it, take off the cover and check the caps on the PS board. Replacing them is not too hard if you have experience soldering. Some devices even have cap kits available because this is so common.
If you replace any capacitors, you want to be sure they are of the proper type; that is, high-temperature, high-frequency, low-impedance capacitors designed for switchmode power supplies, since if you use the kind from RadioShack, they won’t work well (either failing sooner and/or the power supply malfunctions due to excessive impedance). In some cases, a capacitor may even be too good, since SMPSs depend on the output capacitor to stabilize the control loop.