Tuning Stability Issue on the ARP 2600 M – Defective Batch?

Hello everyone,

I’m posting this to alert ARP 2600 M users about a recurring issue with tuning stability that I’ve experienced across three units. After purchasing my first ARP 2600 M, I noticed a significant detuning across octaves. Korg kindly replaced it, but the second unit showed the same issue. I then received a third replacement unit, tested in Korg's workshop, yet it also has major tuning drift—more than 100% over three octaves.

Despite multiple attempts to get an explanation from Korg, I haven’t received a response in months. I’ve decided to share my tests here to see if others have encountered similar issues.

https://www.youtube.com/watch?v=YUE6RDcT-0g

If you've faced similar tuning problems with your ARP 2600 M or have any advice on potential fixes, please share your experience. Thanks for your time and for any help or insights you can offer.