Yamaha CLP-685 Quiet Key

Hello,
We have a Yamaha CLP-685 that has a single quiet key. We had a service person come look at it a while ago, and he cleaned some dust, but it seems to have come back. Is anyone aware of this as an issue?
Thanks!
Josh

We have a Yamaha CVP-809 (1 1/2 years) and have not noticed quiet keys. We also play on a lot of Clavinovas at our local Yamaha dealer and haven’t seen that issue there. Too bad the last service call did not address the issue fully. I wonder if Yamaha customer service or tech support could help? Or perhaps a Reddit search on the topic?

Frank

Both of these may be qualifying for DMI0064 and DMI0113 respectively.

Reply with serial number of the units and I will confirm CLP-695 and the CVP-809