Soundy Plug in – HTTPS

Hi, after handling my webseite with the Better Search Replace plug in, I am getting error messages, with green lock and a yellow screen (mozilla) in the addressline indicating a problem. Getting a screenshot through editor, it indicated that there were apparent problems about the soundy plug in, and by hitting the button for temporary release of the full website content, the play button of the site showed up, being a indication that this plug-in version 3,6 created the insecure address line symbol. Now the plug in is apparently a part of my modfied hemningway website, and has a link address which is an HTTP address of my hosting provider. I did see that the uploaded files do all show up as http and are stored like that (manually changing those addresses to HTTPS did not handle.
I would either a) update the plug in b) deinstall and install the plug in again. Tips about handling otherwise would be great.