jQuery(function($) {
    var $lang = $('#lang').text();
    var $tracks = $('#tracks');
    if ($tracks.length) {
        $.ajax({
              url: "track-service.php?lang=" + $lang,
              global: false,
              type: "GET",
              dataType: "html",
              success: function(msg){
                 $tracks.replaceWith(msg);
              }
           }
        );
    }
});