Audio CDs are different from other data inserts. Audio CDs are stored on a system called the Red Book.
So if you want to insert audio CDs into your computer, you will see files like Track01.cda and Track02.cda which are 44 bytes in size. If you double-click the * .cda file to play it, you will be able to listen to the corresponding song/sound, but if you copy and play the file, you will not be able to play it. If you want to copy music/audio from such audio CDs to your computer, you will need to rip it with some special software.