My EVO Design 4G screen blanks out during calls and listening to voice mails. This started happening a week ago. I've gone through all the settings, I even installed an app called "Screen On'. Didn't help. Also removed the cover, no difference. I do have a screen protector, how ever it's been on much longer than when the problem started. Web searches say it's the proximity sensor. I am in the process of doing a complete back up and then a factory reset, but the reset is a last resort. Any ideas are much appreciated.