The su root might be the problem (have you tried it with sudo?) but I see from 'groups' that you are not in the 'admin' group and I think that might have something to do with it personally.
You can change that from the 'User Accounts' menu entry if you wish to. Click the padlock icon to unlock, then change the account type to administrator.
I can't guarantee that will fix it, but it's worth looking into, if it doesn't work or you don't like the idea, it is very easy to undo.
Fujitsu Lifebook AH532 Laptop. Intel i5 processor, 6Gb ram, Intel HD3000 graphics, Intel Audio/wifi. Realtek RTL8111/8168B Ethernet.Ubuntu12.10 (Unity), Mint14 (Cinnamon), Manjaro (Xfce).