2018-03-21 by flori.weiler@...
Thanks for all the comments. I've found a solution. Initially, I had the VZ-1 connected to a virtual MIDI port using loopMIDI. I've then patched this port to the physical MIDI port of the VZ-1 using MidiOx. I do this for all my synth, to allow running DAW and Editors/Librarians in parallel. MidiOx is the only tool that communicates to the physical ports, all other applications use the virtual ports.
Somehow this must have been the problem. When I directly connect MQ to the VZ, the communiction works. Surprisingly, I can still run Cubase, MQ and MidiOx in parallel, without any driver conflicts.