Users Unable to Download Sermon

I've run into a small problem with Sermon Speaker. There are a number of sermons uploaded and the players work properly, but I can't seem to download a single sermon. Whenever I click on the Download Audio, I get taken to a page that contains bits and pieces of information, but eventually the page locks up and I have to kill the browser to do anything.

After browsing the forums, I made sure that the Google Analytics integration was disabled, and the player is running the most current version as of today (2-5-16). Could you take a look and help me get this issue resolved? You can try for yourself at www.bloomfieldchurch.com/sermons/sermon/399-in-trouble-how

I'm quite sure this is somehow related to your server setup using Nginx.
When I look at the headers done by my Apache the file is served as "Content-Type: audio/mpeg" and there is a header which tells the browser to download the file instead of opening it (Content-Disposition: attachment; filename="2-mose-und-die-plagen.mp3").
With your setup the header is "Content-Type: text/html" and thus the browser tries to open it as a regular HTML page, which obviously is going to fail miserably with an mp3 file.

So you may have to ask your hoster to see how that could be solved.
Another way could be to directly link the download to the audio file instead of going through the download task. But then it's up to the browser what it will do with the file. Most will probably not download it and instead directly play it in the native media player.