Hi Gary,

Press MUNU:
Press F4 KEYBOARD:
Press F5 ACCORDION:
The F8 button is BASS OCTIVE:
Press F8, and then select with cursor. you can go up or down 2 octives.

Don't know if you have the capability to select this function from your accordion.

Also, if I read your post correctly you are getting bass notes when you don't want them. thus you are setting the bass to Ch. 4. and then changing back to Ch. 3.

When in accordion mode as deescribed above, at USER button 3/8, it says BassonStop, or BassoffStop. Set that to off.

Also, I would recommend that you create your manual bass setup in accordion2 and your auto/arranger setup in accordion1. That way you only have to select one thing if you want to play manual press accordion2, and auto press accordion1. Be sure to SAVE.

Press MENU:
Press MIDI:
now USER button 4/9 is accordion1
and USER 5/10 is accordion2

Hope this helps
Don P