This really should not happen, as the device has a proximity sensor that should turn off the screen when the device is held up to your face. If you make a call with the phone held in your hand and you cover up the top of the phone, say the top 2 inches, with your other hand, does the screen blank? It should. If not, the proximity sensor may be bad and a replacement is in order.
Current: Verizon Samsung Galaxy Note II - running the unparalleled Jelly 'Beans' - Build 17 with the Sabre kernel
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