I would look at mp3gain. It is a free program and may do what you want.
Can anyone tell me the best way or the best program to diagnose my mp3 collection? It seems that while most of the mp3's on my Creative Zen Touch sound fine, there are many that sound as if they're underwater (sort of a ''gurgling/gargling'' quality to it).
What I'd like to do is load up all my mp3's into some program's interface and have it scan them and diagnose them, and thereby either fix the damaged files or at least indicate which ones are damaged so I can delete them and replace them with better copies.
Thanx.

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