Sound Issues

Sometimes when tabbing between WoW and the desktop on my computer (XP, 2.5 gb RAM, 80gb HD, 8600 GT) the sound kinda goes static-like, but tabbing between the desktop and WoW a few more times will fix it. Not sure why it happens or how to fix it, but it makes me aggravated. Also, on my laptop (Inspiron E1705, 1 gb ram, 256mb GPU, Vista) WMP (windows media player) will skip. Similar to a scratched CD, it will skip now and again, (but only does it once per song) and only does it to MP3s, not actual CDs, or songs ripped from CDs... Any suggestions?

do all your windows updates on both pc's, critical and software, then download the newest drivers for both your sound cards...