I've tried to convert iTunes files (m4p and m4a) to mp3 using Linux and Windows. I've had great success with m4a in Windows, but m4p, not so much. When I right click on the file and select "Properties," Ubuntu recognizes the file as MPEG-4, but both Ubuntu and Windows don't recognize it when it comes down to conversion. Is there a way that I can tell the conversion program (faad, perhaps?) that the file is MPEG-4? Thanks in advance.