Not my tv but I'm a fixit-guy trying to troubleshoot it for wife's coworker/friend. TV is 2-1/2 years old, and the screen has started flashing off and on constantly whenever it's powered up. Audio works and all menu functions seem to work; you can see everything bright and clear when it flashes on, then completely dark. Already tried replacing the main power supply board (ShopJimmy), with no change. Still has same flashing, every ~1300ms or so. Measured standby voltage at 3.2V. What are the next steps? Is this worth putting more $$ into? Any and all help appreciated!!!