Hum on MAM ADX1 Drummachine (Main Out)

Hello everyone,

i hope i am right here to ask for help regarding this issue.

I bought a used MAM ADX1 Drumachine and am a big fan, especially using it in experimental ways.

Since quite early after the purchase i noticed a 50hz (100,150...) hum. It modulates volume by itself. sometimes louder sometimes not noticeable.

The hum is NOT on the individual outputs only on Main Outs L/R. So is it maybe a summing issue?

I changed already the power supply, cables, powersources, interfaces, didnt solve the issue.

Now i opened the box as it looked quite used on the outside, but the insides are looking super clean and all i could find is one capacitor that maybe got touched by a soldering iron or exploded?

Can some experts tell? Also is it part of a circuit that might be responsible for humming?

I am not super skilled with electronics unfortunately but i definitely could exchange that thing if it could solve the problem?

Thanks for your helps.:cowbell::cowbell::cowbell: I added pictures.

Best,

Mogli









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