разве эти все Require once не на сервере обрабатываются? Какой там аякс?

Так вызывается:

function ap_lsf(u, tr_uploaded)  // load_sound_files
{
  $$.ajax(path + "mp3soundsload.php", 'POST', 'u=' + u, function(sounds) 
  {
    var resp = JSON.parse(sounds);
    var items = '';
    for(var index=0; index<resp.length; index++)
    {
      items += '<div id="player__' + resp[index].audioid + '"><div title="' + 
      sprintf(tr_uploaded, resp[index].flname) +'" id="player_' + index + '"><div>' + 
      resp[index].author + ' - ' + resp[index].title + '</div><table><tr><td><div id="play_button_' + 
      index + '"><a class="player_button" href="javascript:void(0);" onclick="ap_pa(\'' + 
      resp[index].file + '\', \'\',' + index + ', \'' + resp[index].author + 
      ' - ' + resp[index].title + '\')"><img id="img_' + resp[index].audioid + 
      '" src="' + path + 'images/play.png" width="20px" height="20px" /></a> </td><td class="" style="width:200px;"><div class="_auplayer_none"> </div><div class="_auplayer_pos" style="width:0px;" id="progress_' + 
      index + '"> </div></td><td><span id="current_time_' + index + '">00:00</span> / <span id="time_' + index + 
      '">' + resp[index].length + '</span></td><td><a class="command" href="#javascript:void(0);" onclick="ap_da(' + resp[index].audioid + ');">×</a></tr></table></div></div>';
    }
    var items2 = '<div id="volume_inner"><a class="command" href="javascript:void(0);" onclick="ap_dec();">-</a> <input type="text" id="volume_value" value="0.5"
    style="text-align:center; width:50px;" disabled> <a class="command" href="javascript:void(0);" onclick="ap_inc();">+</a></div>';
    $('volume').text(items2);
    $('sounds').text(items);
  });
}