I have a bunch of 7921G phones that are stuck in headset mode.

I was able to RMA only a few of these phones - hardware problem.

I took one of the non-warranty phones apart, removed the entire 'headset' port from the phone; from the circuit board (hoping there was something makeing some sort of contact that told the phone a headset was plugged in).  I have factory defaulted the phone and upgraded to the latest 1.3.4 OS... the damn thing STILL says headset mode!!

Is there any engineer out there who can tell me how this is possible when the entire thing is removed from the circuit!?  There has to be a way to fix this, rather than throw $5,500 worth of phones in the garbage!!