tablesorter plugin - behavior with ajax

tablesorter plugin - behavior with ajax

Using the tablesorter plugin: http://tablesorter.com/docs/

TL;DR: How can I prevent tablesorter from caching data when a new ajax call is made? Or how can I clear tablesorter's cache when a call is made?


I am sorting a table populated with data from an ajax request. Depending on where I initialize tablesorter, I run into one of two problems:
  1 - If I initialize based off the click event that fires the ajax and then trigger a sort in the success function, it doesn't sort on the initial data, a header has to be clicked to initiate the sort. 
        Example:
            event to fire off ajax call:
                  $('#id_department' ).change( function () {

                timer && clearTimeout(timer);

                timer = setTimeout(create_post, 300);

                $('#results').empty();

                $("#results_table").tablesorter({debug: true } );

         });

        on success:
                  var sorting =  [[0,0 ] ];

                $("#results_table").trigger("sorton",[sorting]);


  2 - If I initialize the sort in the ajax success function rather than before the ajax call, the initial sort is correct, but if I fire another ajax event, which clears the table and repopulates it, tablesorter keeps the cached data from the previous call and ends up doubling up a lot of the data. 
  Example:
      ajax success:
            ...
            $( "#results_table").tablesorter( {debug:  true } );
             var sorting =  [[0,0 ], ];
            $( "#results_table").trigger( "sorton", [sorting ]);


How can I prevent tablesorter from caching data when a new ajax call is made? Or how can I clear tablesorter's cache when a call is made?