Remove old content types from Moodle

Hello there, I was wondering if any of you knew how to remove content types previously installed in Moodle.

I haven't found any option to do so from Moodle itself, and I was wondering whether it could be done from the server or someplace else.

The question arose when one of my teachers noted that some of the content types we have are not listed here anymore:

Does that mean that they won't work properly anymore?

Problem with Audio content type upload?

Hi there,

It seems I can no longer upload files through the Audio content type uploader.

The last time I successfully uploaded was 14 days ago (4th Dec 2018).
I wonder whether this could be related to the new Wordpress version 5.0.1 or the newest update to the Audio content type.

When trying to upload a file, I receive the error message: 'The file you are trying to upload might be too large'.
This error message comes even when uploading files as small as 100kb (I was succeeding before with files of upto 1.5Mb) so I'm sure it's not really related to size.