Using Sudo
sudo allows ordinary users to access system utilities normally only available to the administrator.
This worked on dyne:bolic 2.5.2. All this needs to be done as root. After creating your user:
1) create a group called admin with the command:
groupadd admin
2) edit your sudoers file with the command:
visudo
find the line where it says 'uncomment to allow all people in group wheel to run all commands'. Uncomment the line below (by deleting the #) Change 'wheel' to 'admin'. Save & exit.
3) Edit the file /etc/group. Find the line for admin & add your user name
(if there is more than one name separate them with commas (don't forget to add the default dyne:bolic user account 'luther'!). I added my name to all the groups that luther was in (I think you need to join the audio group to get real time privileges & access the mixer)
4) Exit X & then completely log out by typing exit. Log back in again & use command startx
After this your normal user password should work in the adminstration password dialogues.