different priviliges in run levels 3 and 5

I noticed that thare are different default priviliges for the user depending if I boot in run level 3 or 5. Normally I use init 5 and login in graphical mode straight to Gnome desktop. Then all my USB devices (memory and external USB sound card) are accessible and work. If I log in throught termina (init 3) then USB has to be mounted and the sound card is not recognized.

Is there any general rule for such behaviour? If I plan to use level 3 shall reconfigure the system go get immidiate acces to usb sound card? Any recommendations, please

The mechanism to provide the end-user with some control over devices that normaly are to be controled by root is designed to work with the Desktop software (KDE, Gnome).
Thus as soon as the end-users is not running such a DE, he has to ask the system manager to, well eh…, manage.
Also think over the fact that multi logins in the CLI are more likely then in the GUI (at least on a desktop/laptop PC). (But even in the GUI with multi logins there is the (unresolved) question of who of those sessions/users will be the owner if a newly plugges in device).

A bit of this is explained at SDB:Basics of partitions, filesystems, mount points - openSUSE.