Locks when making a call.

I've had my G2 for about 2 months, today I started having an issue where most phone calls (in or out) result in the screen going completely black and not being able to access it.  None of the buttons will unlock it.  I have to wait for the other person to hang up.  After the call ends there is a 20-30 second delay before the phone unlocks it self and becomes usable again.  It's happened on most of my calls today.  Restarting the phone seems to buy 1 or 2 functional calls. 

I do have a screen protector, no case.  Assuming the proximity sensor is the black spot between the camera and the speaker, the screen protector is no where near it.  The phone has operated flawlessly for a month with the protector on it.

Re: Locks when making a call.