Well, that's a little off topic, but YAMAHA has a more powerful MIDI implementation than SG.. it's XG.
You can have drums on any track you want, Even in a style.

OK, now back to the original problem, sequencer getting sound from Part you record. Look at it this way, there are 4 parts, but 16 tracks. So it's very annoying to change sound back and forth.

Any help?