Fixed my Proximity/Ambient light Sensor
Hi, I had this problem since new and I tried installing lots of stock and custom roms (Stock US, Stock SP, Stock TW, Miui, CM11) but it was until I installed EXISTANZ rom, and a hard reboot, and then it magically started working. I knew it wasn't a Hardware issue because when the phone boots it worked for few minutes, then stop reading samples. But I've been with this rom for 3 weeks and I don't have any problem with this (Already installed and update, reset the phone and still working).
So if you have the chance, install this rom.