Noise issue?

[zaklinacz]

Hello all,
In the past I've builded 1 MD from Synthex kit which is working very good. Then I've decided to make another 2 (for Zendrum-like devices) from scratch. So right now I have 2 digital and analogue boards ready. The problem is that on one digital board I have some very strange issues. When this board is not connected to analogue part averything seems to be stable. The problem appears what I'm connecting analogue board. I'm getting random notes from midi out, when I'm hitting piezo sometimes I'm getting 3 notes at the time (but always the same notes), some inputs seems to be not working at all. After some time MD is not responding to any of the hits, then after some time it starts to work again (but with the same problems). The problem is not in the MCUs (I've changed them with the ones from working piece, and these from "wrong piece" are working flawlessly on good one) or analogue board, which is working very good with another digital board.
The only difference between the boards is that one set is built on copper only PCB (the wrong one) and another is tinned.
BR
Michal

[zaklinacz]

Problem solved - small short in analog connector area on digital board...
BR
Michal