Ok. Here's what I ended up doing to get Sound working reliably under Knoppix 3.3 on my Thinkpad 600, and why.
But what should I have done?

The module needed is the cs4232 (and opl3 for midi).
This seems to get loaded, but without any options, at boot, sound doesn't work, reporting an error with /dev/dsp.
Adding the correct options to modules.conf, via /etc/modutils/sound had no effect (this is how I thought it should work... Weird).

So I've ended up with the following script symlinked to rc5.d as S98 (prior to kde loading).
Code:
#!/bin/bash
rmmod cs4232
rmmod ad1848
rmmod uart401
rmmod opl3
rmmod sound
rmmod soundcore
modprobe cs4232 io=0x530 irq=5 dma=1 dma2=0 mpuio=0x330 mpuirq=5 synthio=-1 synthirq=-1
I didn't bother with midi, but that would be
Code:
modprobe opl3 io=0x388
I found that this has to be loaded prior to the gui starting as kde attempts to initalise sound and then you can't rmmod the modules.

Does anyone have a more elegant solution, or advice as to how to do this properly?

Cheers