Se la versione di udisks2 è > 2.0.91:
c'è un parametro apposito di udisks2 che si puo' passare tramite una regola udev.
"you can tell udisks2 to automount in /media/ instead of /media/[username]/ by adding a udev rule that sets the environment var UDISKS_FILESYSTEM_SHARED. You can do this by adding a file called (eg) /etc/udev/rules.d/99-udisks2.rules that contains:
ENV{ID_FS_USAGE}=="filesystem", ENV{UDISKS_FILESYSTEM_SHARED}="1"
I think udev monitors the /etc/udev/rules.d folder to detect changes, but if not, you can force it to reload its rules with "sudo udevadm control --reload". Note though that the new mount location doesn't seem to take effect until you physically remove and plug the external drive back in."