hey subq
I keep reading your post and still more questions …
t uses the sound of the track instead of just using the voice for poly
do you mean [u]TRACKS /u … what is the difference between track and voice?
try creating a bunch of different sounds on each track, then turning that on with poly and selecting the voices 
turning THAT on, what THAT? with poly, huh, with poly? where to press what? in which menu? … selecting the voices, which voices to select where?
sorry for being undereducated … 