I had that problem after I did an ota upgrade. While I would be on the phone it would randomly call out to anyone that was in my phone log. I had to wipe my phone and reinstall the os from pc and it fixed the problem. Hope it works for you.
Posted from my CrackBerry at wapforums.crackberry.com
having the same issue and it's really annoying. Running the 7.0 OS. Is this bugged or something? Is there a setting to have it lock screen while on the phone?
found the problem - screen cover on phone = proximity sensor doesn't work. Just to the left of LED light. If you have a screen cover just cut a small area there - should solve the problem. Your screen will go dark when you are on a call and you won't be able to hit any of the touchscreen buttons (hopefully?
Last edited by serafinatoyou; 02-22-12 at 05:48 PM.