Randomize packs sounds only?

Hello , when i click the randomize sounds im not sure but i think randomization only affects the factory sounds because i don´t see sounds from a pack in that randomization. I would like to know if it is possible to randomize ONLY the sounds from a pack ( for example “voltage pack”) and not the factory sounds. By the way don´t know if is possible randomize all sounds , i mean factory sounds + packs together and not only the factory sounds. Thanks very much.