mysterious problem

I love the functionality and the stylish design of the plugin, but unfortunately I am close to giving up.

It seemed that a former problem had to do with the characters of the url. But now I have on one page a link like: https://s3-eu-west-1.amazonaws.com/something/somethingelse.mp3 and it works and another link with the same structure on another page and it does not work.

The only visible difference is that the working link has also a video on the page, where as the failing link has some other audio shortcodes on it for a another plugin which is deactivated. Are these shortcodes the problem? I suppose not because I published the link on a fresh page with nothing on it and it does not work. I updated my test site to WP 4.0 and it does not work either there.

I can´t find a consistent error pattern and I am close to giving up. Any helpful hints?

Thanks,
Demian

https://ww.wp.xz.cn/plugins/wp-miniaudioplayer/