My first suggestion would be to check for updated video and sound card
drivers. Go to the manufacturer's website, not Windows Update for this.
Secondly, what version of DirectX do you have? Not sure if WMP10 is
requiring of this, but the latest version is 9.0c If you type "dxdiag" (no
quotes) in the Start|Run box, your installed version is there on the first
page. You can also run a number of tests from here re: sound and video.