On playing a BIAB 2009 Mac song that uses BOSSABRUSHES_ 45_style.m4a, I heard a sound like white noise for 2 seconds.
On opening the .m4a file it was indeed damaged, at 1 minute, 19 seconds.

I thought it was corrupted during my download, but I received the Hard Drive in the mail and the file was the same.

Perhaps a PC User can check to see if the .wav version is O.K.

Thor
Tampa, FL.