[Biturbos4] B5 nav reset?

[Rich Shiba]

Anyone know how to reset the factory Audi Nav unit?  Mine kinda quit
responding to the "Nav" button (i.e. it won't activate anymore).
My first lame reaction was to power cycle the thing, but i can't
figure out if there's a way to do that short of removing it and
pulling the wiring harness out of it.  Any thoughts?  It's pretty
much not responding to anything -- hitting the eject button on the
front panel doesn't illicit any response...

      -rich,  2000 S4
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