I just recently upgraded to Anki Version 2.1.33. Before, when I added media (mp3) to a note, it would automatically play. This was helpful because then I could make sure the mp3 actually played what I thought (there have been a few times where I mislabelled the mp3, and it was different than what I thought it would be.) This is the first time I’m adding media files to notes, and they are not automatically playing when the note is formed. They do, however, play correctly when previewing or reviewing.