tablesorter cannot read property '0' of undefined with data

Question

Hi I have a table dynamicaly filled (via php and jquery) but the tablesorter does not work Scripts initialization at the end of the page

<!-- JavaScript -->    
<script src="js/bootstrap.js"></script>

<!-- Page Specific Plugins -->
<script src="js/tablesorter/jquery.tablesorter.js"></script>
<script src="js/tablesorter/tables.js"></script>
<script>
function dynamicRefresh()
{       
    //generic
    $(".pm-count").load("php-scripts/dynamic/pm-system/countU.php"); 
    $(".pm-ddmenu").load("php-scripts/dynamic/pm-system/menu.php");
    $(".com-count").load("php-scripts/dynamic/com-system/countU.php");
    $(".com-ddmenu").load("php-scripts/dynamic/com-system/menu.php");
    //Page Specific
    var lpage = page - 1;       
    $("#new_msg").load("php-scripts/data/setlist/table.php", {'page':lpage});       
    //Refresh Rate
    setTimeout("dynamicRefresh()",60000);
}   
window.onload=dynamicRefresh;
</script>

Table Code

<table class="table table-hover table-striped tablesorter">
                <thead>
                  <tr>
                    <th>Ordem # <i class="fa fa-sort"></i></th>
                    <th>Nome <i class="fa fa-sort"></i></th>
                    <th>Banda <i class="fa fa-sort"></i></th>                       
                    <th>Original/Cover <i class="fa fa-sort"></i></th> 
                    <th>Ac&ccedil;&atilde;o <i class="fa fa-sort"></i></th>                                  
                  </tr>
                </thead>
                <tbody id="new_msg">

                </tbody>
              </table>

I only click to sort the table when the table is filled with data I know if the table has no data this error occurrs. Can it be because of the plugin initialization? The plugin is loaded faster then the table data.

UPDATE #1

After close look at the debug console I see this

Built headers:,1ms jquery.tablesorter.js:147
[th.header, th.header, th.header, th.header, th.header, prevObject: x.fn.x.init[1], context: table.table.table-hover.table-striped.tablesorter, selector: "thead th", jquery: "1.10.2", constructor: function…]

I think it's safe to assume that when the plugin is initialized it builds the headers but also loads the data to faster sorting, if this is correct is there a function to "update" the initialization process?

UPDATE 2

After reading some more I found that I just need to add a trigger in this case

$('.tablesorter').trigger('update');

It's working fine now