After updating to the OTA 4.3 my S3 now has a glitch causing the screen to occasionally black out, mostly during phone calls but also after screen timeouts when i hit the power button to turn the screen back on it'll stay black for awhile, the menu and back buttons light up and the touch sensor still works even when black. it work flawlessly before the update. I tried to root and was successful at it using the saferoot method but because of the know being lock I can not install a custom rom or recovery and the problem was still there because I was still using the 4.3 rom. So I used odin3 vs3.07 and put the stock rom back on and unrooted and the problem is still there. does anyone know how to fix this glitch or does anyone know how i can go back to the 4.2.1 rom or install the 4.4.2 rom because 4.3 has been nothing but a headache for me.