Just wondering...almost all of my music files are file type M4A, which I take to be ALAC (since that is the encoder setting I use for rips). But, I have recently noticed that some of them (complete albums in every case) are MP4's. Interestingly, the MP4 file name only seems to be for albums that I ripped over a ten-day period back in June. Could someone explain what this means in layman's terms? And do I need to change the file extension, or leave that MP4's as they are (obviously both types of these files play normally)? Thanks.
