… thanks for spotting this 
. In fact, I think I am correct in saying that this only happens when those controllers are active in the new VST Quick Controls… they still pass through ok in the original Track Quick Controls.
(Here, both Track Quick Controls and VST Quick Controls are fed by a separate MIDI input port from the one used by my external MIDI Keyboard anyways, so, in “real life”, I never come up against this situation 
)