Sound - sometimes works, sometime doesn't on SigmaTel

[Ariod]

I've got an Intel motherboard with an integrated sound card. It's SigmaTel STAC9220D/9223D.

I've got a weird problem. Sound sometimes works and sometimes it doesn't. I usually open up XMMS to see if it works. When it doesn't, XMMS gives me the following error:

Please check that:

Your soundcard is configured properly
You have the correct output plugin selected
No other program is blocking the soundcard

Then I just restart (sometimes a few times) and the sound works again. As if FC5 "forgets" to load the drivers.

What could be causing this?