My phone has started acting up, again.... It now no longer turns the screen off when held against the face. The screen will stay lit for about 2 min then goes black. When the call is done it remains black. I have to hit the power button for it to come back to life. There is nothing covering the sensors and the screen is clean. I did a pwnage restore of 2.2.1 but no luck. Anyone face this same issue?