iTunes - M4p (protected files)
Most file formats found and used in iTunes can be directly used in Song Surgeon. For example: mp3s, aac, wav, m4a, mp4can all be opened in Song Surgeon. M4P file cannot because these are protected files.The work around for these protected files is to export them and save them in a different format. You can Export these songsusing iTunes and save them as mp3s which can then be opened in Song Surgeon. Here is a link that discusses how to export from iTuneshttp://support.apple.com/kb/PH12167