It had to do with the order in which the footer was being called. (The footer was being called in the wrong place in the single.php page.) My apologies! This has been fixed.
Wow. Thank you to lgedeon.
This has been troubling me for weeks! As you suggested, I put the <?php wp_footer(); ?> right before the </body> tag and it worked beautifully!
Cannot thank you enough!
Can I just say that you are a freakin’ rock star! I have been trying to get videos and mp3s on my site for way longer than I should have and the above is awesome.
Thank you!