tumblraudioreplace.js

$.noConflict();
jQuery(document).ready(function($){
  $('.audio').each(function(){
    var match = $(this).find('script').html().match(/audio_file=(.*)\\x26/);
    $(this).find('span').html('<audio src="'+match[1]+'?plead=please-dont-download-this-or-our-lawyers-wont-let-us-host-audio" controls="controls">Your browser does not support the audio element.</audio>').remove();
    $(this).find('script').remove();
  });
});

Just for the record, I love the URL disclaimer.