trouble connecting

Same trouble here!

When using the Embed Media Player option from the Add Media page––
[audio mp3="https://www.lewesvoiceworks.org/wp-content/uploads/2013/12/Drinking-Catches-1.mp3"][/audio]––
the player buffers continually but won’t play the file.

Elsewhere on the site Audio Player works fine but the code is like this:
[audio:https://www.lewesvoiceworks.org/wp-content/uploads/2013/12/Drinking-Catches-1.mp3|titles=Purcell Catch No. 1]

How can I get the Embed dropdown option to work correctly?

https://www.lewesvoiceworks.org/

Thanks!
Paul