Hi there,
since I don’t use the Send A/B knob on my instrument racks, I tried to repurpose the knob as a quick control for the Wet/Dry ratio of the reverb inside the rack instead. Unfortunately, the knob doesn’t show up as a binding source when creating a binding inside the rack. I think it makes sense to add the knob as a binding point because it’s currently the only “rack slot control” that is not bindable from within the rack.