I've tried to build a four oscilator synth in Polyphone: it mainly seems to work

However, the potentially useful "mute" status on one of the oscilators doesn't save as part of the Soundfont file. I'd like to be able to mute the seperate oscilators for setting up presets.....
... better still I'd like to be able to mute and unmute osciators by controller or sys ex messages sent from a keyboard/external midi controller.
Any help please?