This must be explained somewhere, but I can't find it.

I've some a VST on the Bass track. The instrument plays two octaves below the MIDI notes, so I've pitch-shifted it via Prefs->Channels to get the played notes correct.

I generate and play the song and I hear my Bass, but I still hear also the default MIDI patch, playing at the two-octaves higher pitch. I select "no MIDI patch" and try again, but I still get the original instrument playing.

How does one stop it playing please?

BTW, I notice also that the original instrument is playing something like a quarter second after the VSTi.

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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