i have the same problem, was watching tv turned my head and it was a black screen, i turned it on and off i see white lines come and go, one time i heard some fizzing sound from the speakers, ive watched loads of videos on u tube but they all say its power this and that, im searching the web for a fix! buying a new tv is not an option as i have a feeling its a easy fix.
howtomendit.com for free repair help, information and advice.
Try fixfault.com to fix televisions.