I've lost my sound with the new 2.6 kernel.
The sound tester works, I hear the test sound. But the cd players rumble on without so much as a peep.
Master playback volume in asound.state is at 24.
I didn't have this problem under 2.4 kernel.
Any tips?

Run alsamixer and try all available mixer channels. Unmute them and level them up.

[And I assume, you do have an audio cable between CD drive and sound chipset or you do use a CD player software which reads Audio CDs digitally...]

All I changed was Fedora, from 2.4 to 2.6 kernel, Fedora core 2.
Sound worked fine before, cable or no cable. Haven't opened the computer since then! And the test sound works!
It's never boring with Linux, always something to do!

Doesn't matter whether the test sound works. Sound problems in Fedora Core 2 are not easy to explain, because the new ALSA drivers provide two interfaces: ALSA and OSS for compatiblity with the old driver system in the 2.4 kernel series. The test sound is played with /usr/bin/play, which uses /dev/dsp (OSS). But other parts of the ALSA driver can still be switched off.

Fresh install or upgrade? What do you have in /etc/modprobe.conf? What does /sbin/lsmod print out?

output from /sbin/lsmod

[dad3@oldcomp dad3]$ /sbin/lsmod
Module Size Used by
ppp_deflate 4096 0
zlib_deflate 19480 1 ppp_deflate
ppp_async 8064 1
ppp_generic 20500 6 ppp_deflate,ppp_async
slhc 5632 1 ppp_generic
snd_pcm_oss 41000 0
snd_via82xx 20644 3
snd_ac97_codec 54788 1 snd_via82xx
snd_pcm 69256 2 snd_pcm_oss,snd_via82xx
snd_timer 17284 1 snd_pcm
snd_page_alloc 8072 2 snd_via82xx,snd_pcm
gameport 3328 1 snd_via82xx
snd_mpu401_uart 4864 1 snd_via82xx
snd_rawmidi 17444 1 snd_mpu401_uart
snd_seq_device 6152 1 snd_rawmidi
snd_mixer_oss 13824 2 snd_pcm_oss
snd 39396 13 snd_pcm_oss,snd_via82xx,snd_ac97_codec,snd_pcm,snd_timer,snd_mpu401_uart,snd_rawmidi,snd_seq_device, snd_mixer_oss
soundcore 6112 2 snd
parport_pc 19392 1
lp 8236 0
parport 29640 2 parport_pc,lp
autofs4 12932 0
sunrpc 109924 1
ipt_MASQUERADE 2560 2
ipt_LOG 5120 2
ipt_state 1536 2
iptable_filter 2176 1
ip_nat_ftp 3696 0
iptable_nat 17708 3 ipt_MASQUERADE,ip_nat_ftp
ip_conntrack_irc 70064 0
ip_conntrack_ftp 70576 1 ip_nat_ftp
ip_conntrack 24968 6 ipt_MASQUERADE,ipt_state,ip_nat_ftp,iptable_nat,ip_conntrack_irc,ip_conntrack_ftp
ip_tables 13568 5 ipt_MASQUERADE,ipt_LOG,ipt_state,iptable_filter,iptable_nat
8139too 17920 0
mii 3584 1 8139too
floppy 47440 0
sg 27680 0
scsi_mod 91984 1 sg
dm_mod 32800 0
usblp 9472 1
uhci_hcd 24472 0
ipv6 184672 10
ext3 103656 2
jbd 40728 1 ext3
[dad3@oldcomp dad3]$

My /etc/modules.conf
alias eth0 8139too
alias usb-controller usb-uhci
alias sound-slot-0 via82cxxx_audio
post-install sound-slot-0 /bin/aumix-minimal -f /etc/.aumixrc -L >/dev/null 2>&1 || :
pre-remove sound-slot-0 /bin/aumix-minimal -f /etc/.aumixrc -S >/dev/null 2>&1 || :
# Note: for use under 2.6, changes must also be made to modprobe.conf!

My /etc/modprobe.conf and I did an upgrade, not a new installation
# Note: for use under 2.4, changes must also be made to modules.conf!
alias eth0 8139too
alias usb-controller uhci-hcd
alias snd-card-0 snd-via82xx
install sound-slot-0 /sbin/modprobe --first-time --ignore-install sound-slot-0 && { /bin/aumix-minimal -f /etc/.aumixrc -L >/dev/null 2>&1 || :; }
remove sound-slot-0 { /bin/aumix-minimal -f /etc/.aumixrc -S >/dev/null 2>&1 || :; } ; /sbin/modprobe -r --first-time --ignore-remove sound-slot-0

Don't like the look of that >/dev/null under sound-slot 0, but I don't want to mess with the file without any advice, so if you have time for an opinion, thanks!

That's the important information. You have a wrong /etc/modprobe.conf due to that. I suggest you delete /etc/modules.conf because you won't get back to a 2.4 kernel. Then edit your /etc/modprobe.conf to contain this:

That is, delete the two "install" and "remove" lines from your existing /etc/modprobe.conf and add the two red coloured lines from above. They are responsible for restoring ALSA mixer settings when the system boots and the audio driver is loaded (and saving mixer settings when the module is unloaded, should happen rarely).

Apart from that, it's the VIA82xx chipset again. Really make sure, you run alsamixer and un-mute all available audio channels. Do ordinary audio players work? E.g. Rhythmbox or XMMS (when configured to output via ALSA)?

Also, but unrelated, in your list of kernel modules, there are SCSI generic modules loaded. In case this is because you tried to activate a CD/DVD burner via SCSI emulation "ide-scsi=/dev/hdx" in the kernel command-line of your boot loader, don't do that. It's obsolete with kernel 2.6 and documented in the FC2 release notes. On the other hand, if you have SCSI hardware, ignore this posting.

Well thanks very much. You know what you're talking about. I was trying to copy a music cd, as they get scratched so easy. And my old command line for cdrdao wouldn't work. Under 2.6, my writer is 1,1,0 not 0,0,0. But even that didn't help. Then someone told me to write /dev/hdd, and bingo, works again.
I'll change modules.conf in modules.conf .old, junk the original, then see what happens. Thanks for your trouble.
I'll let you know if it works.

I am using with Gnome.
I checked out grub.conf
There is no reference to ide-scsi anywhere, so where is that coming from? An init script??

Haven't tried xmms yet, but will do. It is not installed at present

Then that part of your configuration is fine. Don't worry.

Well, the good news is, I've got sound now thanks to your advice. For some reason I haven't got much volume even with it on max, but it is loud enough for me.
So thanks very much for your help, and if I can do anything for you, just email!