I have the same problem with sound in this latest knoppix version. I have an A30p Thinkpad laptop which uses crystal AC'97
Audio Controller Type Intel 82801CAM ICH3-M
Codec Name Cirrus Logic CS4299.

I used the alsa option and though it seems to load the alsa driver nothing appears in the modules.conf that relates to sound.

If I run snd-config I can get sound but not through alsa.

I have a hd install of knoppix 24/9/2003 and sound works perfectly with that version, so something must have been changed in this newer version.