Hi
There is sound on WMP, so no problem there with any volume.
I tried all of the codec installations, still it dit not help at all.
I even went and update WMP to 11, in the hope it will find the fault, but still even that did not help.
I reckon a simple problem like this may ask for a re- install of xp to solve this.
I just remember, that ever since updating IE 6 to IE 7, the volume icon disappeared from task bar, now that tells me something is wrong with the browser, as the missing sound is only when I am using a browser to try to listen to stuff. On the other hand, even this does not make any sence, as with FF it is the same problem.