Could be a bad gate driver IC on the panel or an inverter IC failing to deliver proper power to the gate driver intermittently.
Another scenario could be a flawed LVDS cable, in either case the TV will need professional servicing, if it is still under warranty take it back.
This can be caused by an error in manufacturing, bad inverter IC on the gate drive board, or if the TV has been moved aggressively or something knocked up against it.
LCD TVs are extremely delicate around the panel area.....
If you need a technician, here you are a tech service website www.tvrepairjacksonvillefl.com
edward, December 2012
