Farfisa Fast 4 with huge background noise

[pabloevaristo]

Hi there! I'm looking for help. what could be happening to a Farfisa fast 4 with a continuous high pitched noise?.
Once you power it up, it's always there. All the notes and buttons are working but the noise is there.
I'm good with electronics so I'm wondering if I could repair this.
LINK TO THE VIDEO


LINK TO THE SCHEMATICS

Thanks!!

[Jason]

Maybe some grounding might take away that noise but that is a combo organ sound noisey but beautiful in all its vintage glory.

[Jason]

It might be your filter capacitors that are supposed to filter off some of that noise.the usual suspects on these are the caps are dried out.