I'm not sure this is an error as such, or at least not a technical one. It wouldn't surprise me if they actually designed this particular instrument to favour dom7th like that for this particular style (where dom7th are quite common).

But since you prefer absolute interpretations, then you should start by turning "Chord Embellishment" OFF while you're generating the song! Then freeze just the piano if you like to still have embellishment on for the rest of the instruments, and generate the rest.
And if that still doesn't suffice, then also set the piano track to Simple, which should absolutely clinch it.


Just because you can, doesn't mean you should!
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BBox 2022 Audiophile, Mac Pro Intel, OSX 10.6.8, 800x600 (TV VGA)