There are thrid party conversion apps that do this kind of of stuff, but but here is how you can do it in GarageBand.
- Create a new Project
- Create an Audio Track
- Drag the CAF file from the Finder onto that Track
- Select the Audio Region (make sure the Cycle Mode is ot selected
- Use the command from the Menu: Share ➤ Export Song To Disk...
- On the Dialog Window select the mp3 option and the checkbox "Export cycle area ...."
- Click Export
Your exported file will have an added 2s silence at the end, courtesy of GarageBand (if you don't mind).
Hope that helps
Edgar Rothermich
http://DingDingMusic.com/Manuals/
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