I had this problem on a pc monitor--turns out there was an IC that consisted of an NPN and PNP transistor all in one chip and half of the circuit went bad. I have no idea if there would be a similar setup inside your toshiba.
I would check the caps first and see if any are visibly leaking ( i have had this on a few tv's that I picked up for free) They may not be domed but look for wetness/glossiness on the board. have you done a search on sci.electronics.repair? sometimes someone has had the same problem and posted results.