Half the trouble is that so many things appear to be interacting, that it's hard to say what causes what.

I now have:
Kontact VSTi on bass track.
Kontact VSTi on Guitar track.
Kontact VSTi on Strings track.

Each is its own copy of Kontact.
Each are set to re-route MIDI to channel 1.
None are set to re-route to MIDI plugin.

If I set the volumes of al tracks to ~90 and regenerate I get both VSTi and another instrument on most, though at the moment I have no VSTi playing on the Guitar track ... I know not why ... the instrumnent shows keys playing.

If I set the volumes to zero and regenerate, then raise the volumes, I get the VSTi playing, but not the other instrument, except that guitar track which now remains silent.

Attached Files (Click to download or enlarge) (Only available when you are logged in)
MIDI-Audio-Driver.jpeg (90.23 KB, 153 downloads)
re-route.jpeg (109.12 KB, 153 downloads)
Jazz relative beginner, starting at a much older age than was helpful.
AVL:MXE Linux; Windows 11
BIAB2025 Audiophile, a bunch of other software.
Kawai MP6, Ui24R, Focusrite Saffire Pro40 and Scarletts
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