i have a gv42lfhdtv10a i bought recently cheap. it has a new main board and powerboard, replaced by vizio. ok, 1 week after this happened, the screen went black, but had sound. so i changed the inverter board, worked great, 2 hours later, now the screen will flash, the sound will cut out, and then the screen will turn black, and no sound, but vizio logo is still white, after a couple of minutes you can turn it off, and then back on, and the backlight works and the video and sound, but after a few minutes again, the screen will flash, then turn off, the sound will stop, and the backlight will turn off, with a white vizio logo still. have tested several things, all u8,u9.u33 and j1 tested good on mainboard, all cables have been cleaned and reseated, all fuses on mainboard and powerboard are good, the 2 fuses on the inverter is good, does anyone know what is wrong and how to fix it?