actually, I found a guide online that discusses optimizing windows xp sound settings
Windows XP Audio Playback - Setup Guide - Benchmark
Set "Sample rate conversion quality" to 'Best'
If you apply the recommendations in this guide, you should be able to avoid sample-rate conversion. However, it is still a good idea to set this feature.
To set this, open your "Sounds and Audio Devices" window from within the Control Panel, then continue as follows: