Here's what I wrote to Elektron support a few months ago:
> if I press Function and turn the Level-knob, all 16 parts become
> louder or quieter. Is there a way to group different parts together so
> these parts can get louder or quieter together (pressing
> Funktion+Level) instead of all parts?
They have added it to the wishlist. But since this is the official wishlist I'll post it here also