Kitkat screen issue

[Insan Hilang]

24-03-2014: i already update android OS to Kitkat OS on my samsung S4 phone..sometime when i watching video(youtube/FB) my screen become crash(look like tv cable crash)
need help thank..

ref :

 

[TowersVault]

Hey, sorry to hear about the glitchy S4.

Try and do a factory reset, just back up before you do it. If the problem still persists, try reflashing the OS using Odin. Odin doesn't root your phone. Head over to Sammobile.com, download version from your country (has to be 4.4.2, KitKat won't let you downgrade), follow the steps and reflash. Hopefully this helps.

(Note: Do the flashing with caution, I've flashed a few Samsung phones and I've never run into any issues, but anything can happen.)