Altec Lansing VS4621 potmeter problems

buenas tardes a todos,tengo el altec lansing vs4621 y me fallan los controles de volumen,graves,agudos no se si alguien tendra esa placa suelta,donde van los potenciometros.

Google translation:
Good afternoon everyone, I have the Altec Lansing VS4621 and the volume, bass, and treble controls are malfunctioning. I don't know if anyone has that circuit board where the potentiometers are located.

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