Radio ON/OFF/VOLUME questions

["John McAvoy" <jmcavoy@purcell-eng.com>]

Hello Friends!

I've seen a number of post in the past covering a problem with
malfunctioning radio On/Off/Volume knobs.  Naturally, I paid little
attention to them because they didn't apply to me.  Well, not anymore.

When my problem first started, the radio in my '93 90S would kick out when
trying to adjust the volume or if I hit a pothole or a bump.  It gradually
got worse to the point where now, the knob 'clicks' but the radio doesn't
turn on, ever.  I explained this to a Audi authorized radio repair shop.
The shop seemed quite familiar with this problem and immediately mentioned
that the knob works off of potentiometers and that this particular one went
bad and has to be replaced to the tune (ugh, sorry, no pun intended) of $120.

My question is this....since I already pulled the radio out of the dash
(thanks to the Q List) is there any way to pull the knob off the face and
perhaps maybe cleaning up the mechanism a bit to confirm that it is an
electrical rather than mechanical problem BEFORE I succumb to dropping 120
beans at the shop?

Thanks for your help!

John McAvoy
1993 90S