I have a Korg TR and the output drops some distortion in all sounds, I restored the factory presets, but the problem continues, it’s sort of a distorted sound, like hissing, is very subtle, but is there, do you guys now how to fix it?
I would suggest you scan the board for bad cspacitors. If they are swollen they are bad. Do check all capacitors in cicuit with an ESR meter. Replace any faulty caps. That should work. Sone caps will ooze electrolyte onto the board and traces ruining the circuits. Examine the buard with a hood magnifying glass.
Thank you, will try, and let you know the outcome.
tantalum capacitors have a failure mode that they don’t show any external evidence of failure, but are shorting to ground. very troublesome to diagnose, but removal from circuit should cause the noise to stop. Replace with an electrolytic type.
Update from the repair: didn’t find the right solution, sold it for a fair price, such a shame, was a good keyboard.