When you use the 'On Controller' call back it will respond when you use any controller #. So if you set the midi_cc to any other number, and have not sent a message on that controller #, then it will reset back to 0 when you touch any other controller. i.e. you need to send a midi message on your chosen midi_cc otherwise voices will reset back to 1 when you touch the mod wheel (or any other controller). I hope this makes sense. Justin p.s. this whole topic ought to be in the Kontakt section of the forum.