Audio player doesn't work with 'audio' posts.

Hello. There was already a post about malfunctioning audio player. But here’s the thing. Now it works only if you don’t ‘mark’ your post as ‘audio’. Otherwise the code of the part where audio should be looks like this:

<div class="mejs-mediaelement"><audio id="audio-player">
<source src="">
</audio></div>

I am assuming, there might be a bug in js-code. And that is totally not my thing, so.. can you please fix it. I am so-o charmed with your theme, I’d really like to use it. And by the way, it seemed to be working on this demo: https://andersnoren.se/themes/baskerville/