function toggleAudioUI(el) {
  el = Element.extend(el);
  el.select('span.audio-control img').each(function(e) {
    if (e.alt == 'Play') {
      e.src = '/images/pause.gif';
      e.alt = 'Pause';
      e.title = 'Pause audio caption';
    } else {
      e.src = '/images/play.gif';
      e.alt = 'Play';
      e.title = 'Play audio caption';    
    }
  });

  el.select('span.audio-control span').each(function(e) {
    e.innerHTML = '';  
  }); 
  
}

soundManager.url = '/audio/'; // directory where SM2 .SWFs live