Okay, I'm missing something obvious. First of all, I must admit I don't remember if I installed Antix 8.0 or 8.2 on this machine. I do know it's using kernel 2.6.27-1-mepis-smp.

I have sound for one user, but not for another. Neither of these users are root. For the non-sound user I get the following results from terminal:

alsamixer
alsamixer: function snd_ctl_open failed for default: No such file or directory

alsaconf
bash: alsaconf: command not found

aumix
aumix: error opening mixer: Success

Despite the optimistic last word of the last error message, I neither see nor hear any success.
All of these commands work with the other user, giving me mixers which I can manipulate. With the non-sound user, I have tried it in IceWM and Fluxbox with pinboard on and off. Please note, the sound configuration option in the control panel doesn't seem to work for either user. That is, it asks for a password, I type in the root password, and then nothing seems to happen.

I have also gone into the Manage Users panel and clicked on repair tab, restore group memberships for the non-sound user. No luck.

Any suggestions?

See what I found

Are you in the sound group? do you have permissions?

Please check the commands:
check that you are in the sound group in /etc/group, AS ROOT:

Make sure you check the volume with the icon in the panel.

teresaejunior and eriefisher, thank you. The location of /etc/group is exactly what I needed. I actually found a file called 'group' and another called 'group-'. I opened each as root and found the sound group teresaejunior referred to. It was actually called 'audio' and looked like this:

audio29:username1

while I was in each file, I just added the user right there.

audio29:username1,username2

I'll never know which file, 'group' or 'group-' was the right one, but I don't care. I saved the files, restarted X, and was very pleased to find sound. Thank you.

You're welcome!