does Anybody know what are ctrl 9, ctrl 12 to 16 for ??
 

As I wwas tweaking sounds and wanted to assign mod parameter to soft knobs, it came to my mind that I never knew what control 12 to 16 are for.

Theses parameters are available in the mod matrix also

Does anybody know if theses parameters are assigned to fixed virus fonctions or if they are user definable data buses like the audio aux 1 and 2?

I would really like an answer on this matter

Use them as mod sources for whatever you want. Then assign one of the soft knobs to send that controller number.

Odd choice of CCs for general mods - thats normally 16-19 (?)

Thanks for the confirmation, these buses will come in handy for those multi-tweak morphing sounds.