[CentOS] Sound problems with CentOS

Has anyone experienced this before? This happened to me even under CentOS
4.x. But basically what happens is that when I play MP3s, whatever the
right speaker crackles at higher volume. And it's always that speaker and
only that speaker. If I turn the balance to the other speaker I have no
problems. So it feels like it might be a mixer issue. I use Alsa, of
course, as that's what the default is. Is this a known issue or does
someone know how to fix it?

Preston