Josh, you should check your sound card's hardware settings, then, if CPU usage is normal. The easiest way to do that is to use the DirectX Diagnostic Tool. Click Start, then Run, then type dxdiag in the window and press OK. The DirectX Diagnostic tool will open. You may be asked if you want to allow checking for digital signatures (I usually allow that - it's harmless). On the first page of the tool (the System tab), you can find information about your computer and DirectX version.

If you click on the Sound tab, you'll see information about your sound card. Is your sound card's hardware acceleration slider set all the way to the right (Full acceleration)? If you test DirectSound, does it successfully pass all of the tests? What is the date listed in the driver section in the upper right? If the date is more than 6 months ago, you should check with your computer manufacturer or sound card manufacturer to see if there is an updated driver available.

The next tab is the Music tab. If you click on the Test DirectMusic tab, does the test complete successfully?