You Mac users probably know about this already, but in case you didn't, go here: http://www.macheist.com/ There's a bunch of software that they normally charge for, only it's freeeeeee for the next few days. No idea what's there - I'm not a Mac guy - but hey, maybe you are. Enjoy!
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From what I can tell from searching the net, it seems like the only way to get around that would be to "rerecord" it. Basically, play it on your computer and rerecord it into a different file at the same time.