Export with flash buttons problem

Example shows problem exporting files using flash. Steps to reproduce: 1. Choose Save button and export to CSV. 2. Click elsewhere to hide flash buttons. 3. Change sorting. 4. Choose Save button and export to PDF. Nothing happens on IE11.

HTML

<link rel="stylesheet" href="https://cdn.datatables.net/s/ju-1.11.4/jqc-1.11.3,jszip-2.5.0,pdfmake-0.1.18,dt-1.10.10,b-1.1.0,b-colvis-1.1.0,b-flash-1.1.0,b-html5-1.1.0,b-print-1.1.0/datatables.min.css">
<script src="https://cdn.datatables.net/s/ju-1.11.4/jqc-1.11.3,jszip-2.5.0,pdfmake-0.1.18,dt-1.10.10,b-1.1.0,b-colvis-1.1.0,b-flash-1.1.0,b-html5-1.1.0,b-print-1.1.0/datatables.min.js"></script>
<table id="example" class="display" cellspacing="0" width="100%">
        <thead>
            <tr>
                <th>Name</th>
                <th>Position</th>
                <th>Office</th>
                <th>Age</th>
                <th>Start date</th>
                <th>Salary</th>
            </tr>
        </thead>
        <tfoot>
            <tr>
                <th>Name</th>
                <th>Position</th>
                <th>Office</th>
                <th>Age</th>
                <th>Start date</th>
                <th>Salary</th>
            </tr>
        </tfoot>
        <tbody>
            <tr>
                <td>Tiger Nixon</td>
                <td>System Architect</td>
                <td>Edinburgh</td>
                <td>61</td>
                <td>2011/04/25</td>
                <td>$320,800</td>
            </tr>
            <tr>
                <td>Garrett Winters</td>
                <td>Accountant</td>
                <td>Tokyo</td>
                <td>63</td>
                <td>2011/07/25</td>
                <td>$170,750</td>
            </tr>
            <tr>
                <td>Ashton Cox</td>
                <td>Junior Technical Author</td>
                <td>San Francisco</td>
                <td>66</td>
                <td>2009/01/12</td>
                <td>$86,000</td>
            </tr>
            <tr>
                <td>Cedric Kelly</td>
                <td>Senior Javascript Developer</td>
                <td>Edinburgh</td>
                <td>22</td>
                <td>2012/03/29</td>
                <td>$433,060</td>
          ...

CSS

.clear {
    clear: both;
}
.datatable-buttons {
    float: right;
    padding-bottom: 10px;
}

JavaScript

$(document).ready(function() {
    $('#example').DataTable({
        "autoWidth": true,
        "scrollX": true,
        "scrollCollapse": true,
        "pagingType": "full_numbers",
        "dom": '<"datatable-buttons"B><"clear">'
            + '<"fg-toolbar ui-toolbar ui-widget-header ui-helper-clearfix ui-corner-tl ui-corner-tr"lfr>'
            + 't<"fg-toolbar ui-toolbar ui-widget-header ui-helper-clearfix ui-corner-bl ui-corner-br"ip>',
        "buttons":[
                        {
                            extend: 'copyFlash',
                            text: 'To clipboard'
                        },
                        {
                            extend: 'print',
                            text: 'Print'
                        },
                        {
                            extend: "csv",
                            text: "csv",
                        },
                        {
                            extend: 'collection',
                            text: 'Save',
                            buttons: ['csvFlash', 'excelFlash', 'pdfFlash']
                        }
                    ]
    });
    $.fn.dataTable.tables( { api: true } )
    .buttons.resize();
});