some time i watch videos my screen getting some kind ok bright lines all over the screen and some time screen become totally black but i can hear the playback sound.after restart it working fine.but later its coming again.anyone know wwhats the reason of this ???? This problem i got after update to kitkat 4.4.2 but i'm not sure its because of kitkat or not coz earlier when i using wechat some times this thing happen but its nt worse like now