I do know that they outsource their repair work for guitar amplifiers, as they have helped me in finding a repair guy. They may be able to point you in the right direction for keyboard and synth repair.
I don't know about repairs but these guys are super helpful.
They don't offer repairs.
Contact The Digital Parachute for all electronic keyboards/synthesizer repair work and restoration. https://www.facebook.com/TheDigitalParachute/
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