Using Audio Player version 184.108.40.206.
Under certain circumstances, the output from function processContent is being filtered by wpautop and it is replacing the "\n\n" with a paragraph tag.
<span>[audio: http://sample.com/sample.mp3 ]</span>
Will result in
<p></span> because of the "\n\n" within processContent.
Perhaps output that might be filtered by wpautop should not output double newline characters?
Thanks for the great plugin, otherwise.