I'm running RH 9.

I don't use sound much, but when upgrading to kernel either 2.4.20-18.9 or the previous one 2.4.20-13.0 I lost my sound output.

dmesg:
Trident 4DWave/SiS 7018/ALi 5451,Tvia CyberPro 5050 PCI Audio, version 0.14.10h, 07:04:41 May 29 2003
PCI: Found IRQ 10 for device 00:01.4
trident: SiS 7018 PCI Audio found at IO 0xd800, IRQ 10
ac97_codec: AC97 codec, id: CMI65 (CMedia)
AC97 codec does not have proper volume support.

What does "not have proper volume support" mean?

modules.conf:
alias sound-service-1-0 off
alias sound-slot-0 trident
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 || :

I've seen this problem a lot. Did one of the new kernels break the AC97 codec?

I really don't want to install ALSA unless I have no other choice.

Followup Note.

When I use the mixer in KDE to load arts, I get this message:

Sound server warning message:
Can't set real-time scheduling priority.
You need to run artswrapper as root or
setuid root. This means that you will
likely not be able to produce acceptable
sound (i.e. without clicks and breaks).

And... running artswrapper as root doesn't do anything either

I had a similar problem, but in my case the ac97_probe_codec would say "Primary codec not present" and of course, nothing worked.

I temporarily solved the problem by copying the "trident.c" file from kernel 2.4.19 into the 2.4.21 sources. The kernel compiles ok and the sound works again.

I'll probably try to find the exact problem when i get some time.