Heil adapter, part deux

[KR4DL@aol.com]

I've had a couple responses indicating the standard Yaesu adapter worked fine
with writer's MP.  I'm baffled.  I thought I would disable pin 2 and opened
the adapter.  The only wires connected in the adapter are pins 8 (mic), 7
(mic gd) and 6 (ptt).  I tested the adapter from both ends and it seemed to
check out.  No reason why it shouldn't work, right?  Tried using it again
(and again..).  Whenever the adapter is plugged in virtually all the buttons
on the radio are disabled, whether the headset is connected or not.
 Unplugging the adapter promptly "fixes" it.  The hand mic works fine (has
connections to every pin).  What the Heil is going on here?  Appreciate any
ideas.
73,  Steve  KR4DL