Your CPU needs a certain amount of time to process audio samples. We recommend that you optimise your computer for audio processing and disable any unnecessary applications.
For more information, please read the guide to “Optimizing your Windows PC for audio”.
S800 ports suffer a performance decrease after installing SP2. This issue is known to affect XP running under Boot Camp on Apple hardware.
You can resolve this by applying Microsoft Hotfix KB885222
If you upgrade to Service Pack 3 after installing Hotfix KB855222, you may also need to apply Microsoft Hotfix KB955408