I have no idea if this will help, because I use v9.1 slackware.
This version is quite finicky about sound. I'm not the one who came up with this command, it was my Dad.
I have to go into root and type this command:
chmod 666 /dev/sound/*
The command makes it so all users can perform the read and write function for sound.
It only works as long as you keep the computer on. When you restart, it needs to be typed in again.
I hope this is useful to you. If not... It was worth a try.