Anyone ever heard of this Mac preamp problem?

[mark1101]

Mine is a C220 having this issue.

The display is garbled with all sorts of unusual characters........when rotating the input selector. The unit still appears to work. At times it comes on by itself.

I have tried the reset procedure and it doesn't change anything.

Some display s are normal such as at power up it says "Tube warmup" correctly. The remote brings up some normal displays as well such as trim and balance.

For the most part, when it is playing I can't see what input is active. Have to go by the sound.