Calling features failed after android download

[bre13]

Was so excited about getting my x10. Have gone through 3 now. Ordered a refurb from AT&T. Phone seemed to be working fine until I downloaded some free apps from the android market. A Stopwatch & Timer from sportstracklive.com. From what I can tell it was after this that the phone started freezing up when use the call features. The screen goes blank and phone locks up. Will not even power off without taking the battery out. Have done the factory reset and repair software with PC companion. Any other suggestions?
There was even a comment from another X10 user that said it worked great on their phone.