My brother has had the AT&T Branded Nokia E71x for about a year now. He is able to text, e-mail, browse, and use just about every feature of the phone except what the phone was originally designed to do; make calls.

Whenever he sends a call, the phones screen goes black, then shuts down completely. The same story right when he presses the answer button upon receiving a call. We have updated the firmware, even tried flashing unbranded firmware on, but nothing has changed. It occasionally works fine, but most of the time its the same ol power down story. Any help would be greatly appreciated.

Could it be a hardware issue? Faulty antenna?