Greetings! I bought a Mother-32 last year, and at first it sounded fine, zero issues. Then I had a three month break from using it, and the next time I powered it up, it sounded really horrible. I checked the frequencies in a tuner plugin, and they were extremely out of tune. I tried to follow the calibration instructions in the manual, and I did manage to slightly improve the tuning, but then the 'KB CV Gain' trimpot stopped budging so I ended the calibration there to avoid breaking anything. At the moment the frequencies look like this when the frequency knob is in middle position:
A5 420Hz
A#4 443Hz
B4 466Hz
C5 491Hz
C#5 518Hz
D5 546Hz
D#5 575Hz
E5 606Hz
F5 638Hz
F#5 673Hz
G5 709Hz
G#5 747Hz
A6 787Hz
And yes, I always did allow it to warm up for 15 minutes before using. Room temperature has been quite stable as far as I know. I also never touched those trimpots before today. This was my first ever synthesizer, so I'm still just a complete amateur and have no idea what might have caused it or what to do now.
Thanks in advance!