ok some1 helped me to find the problem maybe it will help some of u so here it goes:
You should first understand there are two 'layers'...
the sound server (ALSA or OSS) and the way to connect to the server...(either directly /dev/dsp or using a synthesizer = aRts)
I presume you are running KDE...
Open the KDE Control Center (that thing with quite some config options)
Ther you should search for 'Sound Server' (or something...I can't tell you the exact names coz I don't have my pc in here...)
then there you should be able to configure aRts..
- if your arts sound server is running:
open xmms and open the config box...there you should be able to choose your output options...select the aRts output plugin.
- if it isn't running, start it....usually it's the simplest way for beginners to use linux sount. also check xmms output plugin
If your system is using ALSA sound,
you should download the xmms-alsa plugin on the xmms.org website. and select that plugin as output plugin.
(if your system uses OSS sound the most probably is that alsa will be started by default)
Now to tell you how sound works:
the application tries to open the 'file'/'device' /dev/dsp
if it's already used by another application, you won't be able to open it again...that's why aRts is quite nice...aRts gives you the ablility to manage the different soundstreams and redirect it to the real sound output...
for more info:
ALSA (Advanced Linux Sound Architecture): http://www.alsa-project.org
OSS (Open Sound System) : euh, dunno the location by heart..google it
aRts (Analog Real-Time Synthesizer) : http://www.kde.org/areas/multimedia/