I have several .aa files (audio books from Audible.com) which won't import into iTunes. Even more frustratingly, actually, is the fact that some will import, and some will not. Since there is no other Mac program capable of playing these files (i.e. QuickTime, etc.), it's hard to diagnose what's wrong. Neither Import nor Add to Library in iTunes, nor double-clicking on the file seems to help. iTunes comes to the foreground, but the audio book isn't added to the library. I've tried all sorts of solutions, and it seems to come down to either one of two things: You downloaded format "1" from Audible. Audible offers up to four formats in order of increasing quality and file size. The smallest size/lowest format reportedly will not work in iTunes. You have a corrupted download. This is the one that keeps getting me. The download appears to have completed successfully, but won't open (as described above). If I download it again, it works. Note that thi...

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