ubuntu 12.04 + xfce 4.8: no audio anymore

[Hartmut Haase]

Hi,
from one login to the other my audio has vanished. The hardware is o. 
k., because XP still has audio. I suppose xfce has killed something 
during logout, as it sometimes does.
Where should I look to get audio back?
-- 
Viele Grüße,
Hartmut

Hungerhilfe: http://www.thehungersite.com

Ohne Zensur suchen:
http://suche.amnesty-bergedorf.de
Ökologisch suchen:
http://www.ecosia.de
Googeln ohne Google:
https://www.startpage.com/deu

Das heutige Motto:
Anrufer : "Ich benutze Windows..."
Hotline : "...ja..."
Anrufer : "Ich hab ein Problem..."
Hotline : "Das sagten Sie bereits..."