1. close ALL sound apps including gnomes mixer applet and you may have to close xfce42. run this command to list all sound app's using sound card: lsof /dev/dsp* /dev/snd/*3. all sound apps and mixers closed?4. as root or sudo run this command: rmmod snd- (ask which snd- module to use)5. report any errors from that command?6. if no errors from the rmmod command then...7. as root or sudo run this command: modprobe snd- model= (ask which snd- module and model to use)8. report any errors from that modprobe command?9. if no errors then run: alsamixer and check the mixer settings, and unmute and set volumes10. report any problems unmuting alsamixer controls and setting volumes11. run this command: speaker-test -c2 -Ddefault -twav -l112. report no sound or errors or if you have sound