I don't think the command of the english language is all it could be in that manual.

Where it says

"Press and hold [SET/SHIFT] while pressing the [DUAL/SOLO] treble register to alternate between DUAL and SOLO modes",

could mean "press the set/shift button AFTER you press the dual/solo button"

where what they really mean is:

"Press and hold [SET/SHIFT] then press the [DUAL/SOLO] treble register while still holding the [SET/SHIFT] button....".

Anyway, finally figured out how to do the dual/solo setting after seeing a video where no lights changed when making the switch.

Seems like the organ setting "3rd percussion", either slow or fast is preferable (button 4).

And, using 3.1 Alpine with either LMMMH (2 Red) or MMM (3 Red) seems to be somewhat better (that buzziness doesn't occur when using these register settings, but it does occur when I add in the organ in dual mode).

I'll have to review Dana's advice on that.

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