Why is that that I only can play one sound at the time? For exampel, when Im running XMMS, I dont hear the alert that gaim does when I get a new message.
Im running fedora, I have a nforce 2 motherboard and using the soundcard on it.

This is what dmesg says about my audio:
i810_audio: Audio Controller supports 6 channels.
i810_audio: Defaulting to base 2 channel mode.
i810_audio: Resetting connection 0
i810_audio: AC'97 codec 0, new EID value = 0x05c7
i810_audio: AC'97 codec 0, DAC map configured, total channels = 6

The soundcard can only be used by one application at the same time. To get around this you need to use a sound server such as eSound. A sound server is a software mixer that claims the soundcard, and all sounds that are to be played have to be played through the sound server instead of directly through the sound card. So the sound server mixes the inputs and outputs one mixed stream to the soundcard with all the concurrent sounds in it.

This is the same way sound output works in Windows where the sound server is built-in.

Håkan