at any random time whether my mac is charging or not, i hear a random "swoosh" sound. all i have open is the finder, safari, and ichat. and im pretty sure it is not a buddy sound
It's gotta be iChat, unless you've got any other programs open that use sound effects. Check your iChat settings to see if you've set it up to make that sound when something happens. I can't think of any other apps that use "swoosh" sounds, except iChat.