[Orion] RX problems

[Zivney, Terry L.]

I had no problems with the Orion in the ARRL DX CW weekend, except
for the TRLog-induced problem of the shift key on the keyboard moving
my frequency.  I have that locked out in the logging program now.

However, I had a very frustrating weekend in the ARRL DX SSB contest.
It's probably cockpit errors on my part, but I don't know what I
did wrong.  The radio would be working fine, then I would notice
while tuning around that the background rumbling noise level would be
increasing.  In fact, I would notice that I could no longer decipher
any stations audio!  The frequency readout on the Orion would tune
with the knob, but the received audio would stay the same.  Cycling
the power on/off switch would bring things back to normal for a while.
I spent the last two hours just leaning back in the chair tuning
around 20m hoping to see if I could make it malfunction; of course,
it wouldn't.

Does anyone have any idea on what I did wrong?  

Terry Zivney, N4TZ/9