"...a complete please to use!"
— Cam Hart What They Say

Why isn’t the play button showing on the audio player?

Your host’s server may not be configured to handle SVG files, which the player uses for its controls. Add this to your .htaccess file at the root of your WordPress installation. If that does not help, contact your host.

AddType image/svg+xml svg svgz
AddEncoding gzip svgz