So a customer swaps me out an EVO that I flashed for him for a Droid Incredible. Not too bad either way really.

The main reason for this was that his incoming calls were not causing the phone to ring. I flashed radios, ROMs, wiped, reprogrammed, and everything else.

Seems that DDTM was enabled and the little amount of data going through would not allow voice calls to interupt.

DDTM - Send voice calls to voicemail during active data connection.

This seems only good if you're tethering for something very important. Remember to disable it later!