Anyone here use Nuendo/Cubase with Yamaha DM2000?

If so… at some point during the various versions of Cubendo the ability to move two faders at once when automating resulted in two smooth curves of automation. The behaviour on my system for the past year or two means that moving two faders at once causes full jittering as the system seems to jump between both automation lines periodically causing useless automation to be written. It seems the driver or something cant deal with parallel (more than one fade move at once) automation being written.

Anyone else have this issue? Is it a Windows and Yamaha Driver problem ? (I’m on the latest Yamaha USB MIDI driver).