Fixed
I have figured out my problem at least. My screen would stay black while on a call despite being no where near my face. After using my husband's droid to see why his did not have the same problem, I discovered an app was to blame. I had been using a very cool app called Executive Assistant (always running) as a lock screen (to keep my messages and appointments at my fingertips). Once I told this app to no longer act as a lock screen (or a welcome screen), I have not had the black screen problem after many more trials. I have emailed the developer as well to see if there is a fix so I can continue to use the app. Hope this helps.
I have figured out my problem at least. My screen would stay black while on a call despite being no where near my face. After using my husband's droid to see why his did not have the same problem, I discovered an app was to blame. I had been using a very cool app called Executive Assistant (always running) as a lock screen (to keep my messages and appointments at my fingertips). Once I told this app to no longer act as a lock screen (or a welcome screen), I have not had the black screen problem after many more trials. I have emailed the developer as well to see if there is a fix so I can continue to use the app. Hope this helps.