On my System (Debian Wheezy x64, Gnome 3) I don't have any system sounds. Other audio is working well.
When I go to settings > Audio > Sounds (hope it is called like this in english) as normal user, all sounds are greyed out. However, when i go to this panel as root, I can play all these sounds.
Is it a problem with privileges?
How can it be solved? I will need notifications in Empathy.