Sounds like either a MIDI Program Change message is being sent, or Cubase is resetting values at the end of the loop. If it's something Cubase-specific, someone else will have to assist, but I'd check for MIDI Program Change messages first. Every once in a while I forget and my MIDI controller keyboard sends a Program Change message when I hit a button and voila, that same Bass sound comes up in the CS-80V. :-)