So ... it's been about 2 weeks, I've noticed my screen is blanking out as if I had the phone up to my ear. This is the proximity sensor that does this - and I perceive it has somehow become too sensitive. Simply moving my hand (even briefly) too close to the top of the screen near the sensor causes the screen to black and it shouldn't do this. Has anyone else encountered this issue? Anyway to disable the sensor before I take the phone to a genius bar?