My sound card is Turtle Beach Santa Cruz. I am running Suse 8.2.
I was able to configure the card fine using ALSA, the only problem is when I play MP3's with Xmms the sound and/or player stalls when I do anything else. For instance, if I am editing a text document using Quanta, as I type, the sound periodically stalls and then resumes. Also if I am reading a web page and simply scroll down, the sound again will stall briefly. It seems to happen anytime there is the slightest spike in CPU use.
I am not sure where or how to fix this problem. Any suggestions?
I can't seem to get MP3s play in any other application except Xmms, so I am unable to find out if it is an Xmms problem, or hardware, or something else.

Currently I just run Winamp on my windows machine for MP3 playback, but I would like to be able to play MP3s on my Linux box too.

Could it be that everything is working OK and that your 'desktop' has sounds attached to actions. Check your 'configuration' of your X desktop. You probably have sounds attached to certain functions (contained in a 'theme'). When you do something that requires a 'document close'= sound, your mp3 is interrupted (which mp3's use a bit of cpu cycles also). In the old ISA/386 days, it was quite common for this type of thing.

No its definitly not that. I have an onboard sound card to that would work fine with XMMS, but if any other sound was played, XMMS would stall and I would have to reload the driver. And I don't think KDE even lets you configure the desktop to allow sounds for every time you hit the Enter key.

I just wish I could solve this last problem. Then I wouldn't have to boot into Windows for anything but Games.