Hi Dave
Thank you. You’ve just encouraged me to do a bit of testing in regards to 6th and min7th chords.

My theory on having to play min7th chords in root position ( so that Yamaha recognises it as the min7th) isn’t correct.

Root position plays Am7 chord A C E G
First inversion plays A6 chord. C E G A
Second inversion plays Am7 chord. E G A C
Third inversion plays Am7 chord. G A C E

So guessing I’ll have to be careful not to play a min7th chord in first inversion, or I’ll get a 6th chord, which would mean I’d have the incorrect bass note playing ie I’d have a C playing instead of an A?