Now I've got the visuals working on my new Slackware 10.0 installation, its time
for the sounds. However as soon as I tried to play an audio file with Kaboodle
I got some horrible high pitched tones coming from my speakers. But that was
yesterday, and they are still making the same evil sounds today; despite the
PC being turned off since then!!! Obviously something has started up right
away to control the sound, but just making a complete hash of it. I can't turn
this sound off at all - thank god for volume controls on my speakers.

Any ideas to what causing this painful problem?

Yea, I hate that too..lol
Try turning off your AC97 Codec in alsamixer.

Thanks for that tip, its worked a treat. I hadn't spotted the extra controls off the edge of the window.

Alsamixer seems to default to AC97 on when I turn things on,
is there a way of changing its default settings, so AC97 is off on startup?

To save the current alsa mixer settings type as root
I also had this problem.

*EDIT*
Maybe we should convince shilo to put it in his how i did it all thread and site.