Ssystem tray missing

[Paul Cartwright]

something bad happened, I lost sound ( trying to play a movie..) so I 
rebooted. When I started xfce back up, my system trays, both top and bottom 
are missing. When I do alt-tab I can see the apps that are running, but when 
I minimize them, they just disappear... where do I look for the config file 
to remove/rename/modify??
-- 
Paul Cartwright
Registered Linux user # 367800
Registered Ubuntu User #12459