I created a group called sndusers and used the usermod -G sndusers <user> command to add someone to the group. This worked great, problem is once I restarted it didn't. How do I keep my user in the group? As of now I have to log out of X, type that, then go back in for my sound to work..
this is what i used
no messing with groups
Try gpasswd -a <user> <group>
Unlike sp00n (no disrespect intended,) I cannot suggest you forget about the standard methods of doing things. While it may be a pain, user & group settings help protect your system. Sound systems and programs which access them, are often an easy method for someone to attempt to hack a PC since so many people leave them vulnerable.
Anyhow, I can't verify the problem you mention. When I tested this, it worked fine for me. I can only assume you are doing this as root and have otherwise set the /etc/devfsd.conf file properly. You can quickly verify if the user is in this (or any other) group by viewing the file /etc/group.
It isn't necessary to use the 'sndusers' group. You could select any group ID you desire. The key is ensuring they are set in devfsd.conf and the user is a member. Thus, on a single user system the group could be the same group which your primary GID. I really don't suggest doing this for security reasons.
If worse comes to worse and you can't figure out the command line stuff, try the KDE program kuser, assuming you have kde installed.