how to disable audio and usb mount for users

[abdelkader belahcene <abelahcene@gmail.com>]

Hi,
I want to refuse access  for some users to usb pen and audio.
 
In previous releases (debian, ubuntu , debian-based ..) , it is  enough to remove the user from the group.
that is in /etc/group 
audio:x:29:bela
plugdev:x:46:bela,geol


with  theses lines :  bela can heard sound, but not geol,    for bela and geol  the usb pen is automatically mounted.
But not for nobody else.

It is NOT the case in the new release, I mean, even if I remove a user from the  plugdev  group,  the usb pen is automatically mounted for that user.

thanks for help
bets regards