01/W ProX dead octave

[sourceofuncertainty]

Hi fellow Korganisms,

I have an 01/W ProX 88-key that I've always liked using as a master MIDI controller. It has a great weighted action and is built like a tank.

I put it away in storage for a year or so, and now that I've brought it back out I discovered some strange behavior.

One octave - 12 keys - no longer play, either the instrument's internal sounds or transmitting MIDI messages.

The odd thing is, when I set it up after being in storage I noticed the problem right away. The next day the problem was gone - everything was working again. A few days later the problem returned.

So far, as troubleshooting steps I have:

- Opened the top lid and cleaned everything out with compressed air (it did have some dust and related cobweby gunk in there)
- Unplugged and reseated the ribbon cable connector that runs from under the keybed to the main PCB

These steps haven't helped. The same octave is still dead.

Any suggestions for additional troubleshooting?