ADA preamp

[brewu22]

I have a mp1 and a mp2. Both were working at one point in time. Now both are having problems. Both preamps seem to be not getting input signal, I think. Does anybody have any experience with these two preamps? Or maybe, any commen problems with these amps. Thanks

[Enzo]

Apply a signal and see if it gets to the board.

make sure the rear input jack is not cutting out the front input jack.