I assume you mean in terms of volume? If so, then Windows XP has a built-in function for doing that very thing. As far as I can remember (I'm at work now and can;t check), it works automatically, but if not, empty your Media Library in Media Player, then rebuild it, with the advanced option 'Auto-Levelling' set as on. Hope this helps. If it's a previous version of Windows, I have no idea, and I tried to find out myself, to no avail. Mind you, I didn't know about this site then :o)