Hi there,
Did you only install the 'kernel-ide-2.4.23-i486-1.tgz' package?
Here are the instructions per the Slackware Security email that I received:
<quote>
WHERE TO FIND THE NEW PACKAGES:
+-----------------------------+
Updated packages for Slackware 9.1:
ftp://ftp.slackware.com/pub/slackwar....23-i486-1.tgz
ftp://ftp.slackware.com/pub/slackwar....23-i486-1.tgz
ftp://ftp.slackware.com/pub/slackwar...3-noarch-2.tgz
An alternate kernel may be installed. Those are found in this directory:
ftp://ftp.slackware.com/pub/slackwar...tches/kernels/
ALSA has also been updated to 0.9.8 and compiled for 2.4.23. These
packages will also be required to use the ALSA sound system:
ftp://ftp.slackware.com/pub/slackwar...9.8-i486-1.tgz
ftp://ftp.slackware.com/pub/slackwar...9.8-i486-1.tgz
ftp://ftp.slackware.com/pub/slackwar...9.8-i486-1.tgz
ftp://ftp.slackware.com/pub/slackwar...9.8-i486-1.tgz
The XFS patched kernel requires different kernel modules. If you use
the XFS filesystem and XFS patched kernel (xfs.s), these packages
contain kernel modules compiled against 2.4.23-xfs:
ftp://ftp.slackware.com/pub/slackwar...9.8-i486-1.tgz
ftp://ftp.slackware.com/pub/slackwar....23-i486-1.tgz
<snip>
INSTALLATION INSTRUCTIONS:
+------------------------+
Use upgradepkg to install the new kernel, kernel-modules, and alsa packages.
After installing the kernel-ide package you will need to run lilo ('lilo' at
a command prompt) or create a new system boot disk ('makebootdisk'), and
reboot.
If desired, a kernel from the kernels/ directory may be used instead. For
example, to use the kernel in kernels/scsi.s/, you would copy it to the
boot directory like this:
cd kernels/scsi.s
cp bzImage /boot/vmlinuz-scsi.s-2.4.23
Create a symbolic link:
ln -sf /boot/vmlinuz-scsi.s-2.4.23 /boot/vmlinuz
Then, run 'lilo' or create a new system boot disk and reboot.
</quote>
Try upgrading the kernel modules (and ALSA patches as well) too and see if that helps. Let me know how it all works out.