The problem: the A knob moves/changes value by itself. It happens even when I’m not touching the unit, and if I touch the knob or the back it gets worse (knob jumps/goes crazy). The unit otherwise looks brand new and came with its original box, but I bought it second‑hand.
What I’ve done so far:
I contacted Teenage Engineering support but haven’t had any luck so far.
Fresh batteries and power cycle.
Checked for debris around the pot.
Has anyone seen this exact behaviour and what was the cause?