I am also having an issue with no sound on some CentOS desktop systems. I manage about 3 dozen desktops. These are all Lenovo ThinkCentre systems of varying vintages, but there are only 2 distinct sound controllers among all of them: 00:1b.0 Audio device: Intel Corporation 82801H (ICH8 Family) HD Audio Controller (rev 02) 00:1b.0 Audio device: Intel Corporation N10/ICH 7 Family High Definition Audio Controller (rev 01) On some systems, the sounds is working fine, and on others it's not. It's not a sound controller issue, as I've got sound working on multiple systems with each controller. I've checked the settings in alsamixer and the master is not muted. As far as I can tell, all systems are configured similarly (they were build via kickstart and maintained up-to-date with "yum update" periodically). Here is some info from a system on which sound is working: # lspci | egrep -i 'audio|sound|snd|alsa' 00:1b.0 Audio device: Intel Corporation 82801H (ICH8 Family) HD Audio Controller (rev 02) # lsmod | egrep -i 'audio|sound|snd|alsa' snd_hda_intel 523949 0 snd_seq_dummy 7877 0 snd_seq_oss 32577 0 snd_seq_midi_event 11073 1 snd_seq_oss snd_seq 49585 5 snd_seq_dummy,snd_seq_oss,snd_seq_midi_event snd_seq_device 11725 3 snd_seq_dummy,snd_seq_oss,snd_seq snd_pcm_oss 42817 0 snd_mixer_oss 19009 1 snd_pcm_oss snd_pcm 72133 2 snd_hda_intel,snd_pcm_oss snd_timer 24516 2 snd_seq,snd_pcm snd_page_alloc 14281 2 snd_hda_intel,snd_pcm snd_hwdep 12869 1 snd_hda_intel snd 55877 9 snd_hda_intel,snd_seq_oss,snd_seq,snd_seq_device,snd_pcm_oss,snd_mixer_oss,snd_pcm,snd_timer,snd_hwdep soundcore 11553 1 snd And here is the same info from a system where sound is not working: # lspci | egrep -i 'audio|sound|snd|alsa' 00:1b.0 Audio device: Intel Corporation 82801H (ICH8 Family) HD Audio Controller (rev 02) # lsmod | egrep -i 'audio|sound|snd|alsa' snd_hda_intel 523949 1 snd_seq_dummy 7877 0 snd_seq_oss 32577 0 snd_seq_midi_event 11073 1 snd_seq_oss snd_seq 49585 5 snd_seq_dummy,snd_seq_oss,snd_seq_midi_event snd_seq_device 11725 3 snd_seq_dummy,snd_seq_oss,snd_seq snd_pcm_oss 42817 0 snd_mixer_oss 19009 1 snd_pcm_oss snd_pcm 72133 2 snd_hda_intel,snd_pcm_oss snd_timer 24516 2 snd_seq,snd_pcm snd_page_alloc 14281 2 snd_hda_intel,snd_pcm snd_hwdep 12869 1 snd_hda_intel snd 55877 11 snd_hda_intel,snd_seq_oss,snd_seq,snd_seq_device,snd_pcm_oss,snd_mixer_oss,snd_pcm,snd_timer,snd_hwdep soundcore 11553 1 snd Similar, but not quite identical. The settings in alsamixer, however, are identical. Any ideas as to what I can try next? Thanks, Alfred