Roland HP 1700 dead keys

My Roland HP 1700 has 10 consecutive dead keys in the high 32 note section. The switches have all been inspected and cleaned with no improvement. What’s the next step?

Replace the keyboard pcb’s. This unit is quite old and those parts might not available anymore… check the boards for corrosion/contamInation. This issue could also be a bad cable/connector. If you require a service manual I can email you one.

Thank you very much. A service manual would be of great benefit.

email address please

I would really appreciate a service manual. Email: Thanks for your help!!