Just finished updating kernel to 2.4.22 and now when I log in it is telling me that a program is rejecting sound. Any ideas on what this could be? I checked the sound mixer and it is not muted or lowered. I am running Slack 9.0

A program is REJECTING sound? Is that the exact wording? I've never seen an error like that before. Did you compile/install a driver modules for you soundcard? What soundcard is it?

Sure you've loaded your soundcard driver?

I know this problem... I went through this and it took me a long time to guess what happened. Slackware comes now with ALSA support which will be kernel builtin from 2.6. But the ALSA support installed is meant to the standard slack's pre-compiled kernel. When you recompile your own kernel you'll have to go through uninstalling old alsa (alsa-driver, alsa-lib, alsa-oss, alsa-utils), downloading sources and recompiling ALSA. Every time you recompile your kernel is mandatory that you recompile your ALSA support to the newly compiled kernel. You can grab the sources at:
ALSA PROJECT. the nedeed sources are alsa-drivers, alsa-lib and alsa-oss(if you need oss emulation in any way)