Remove attribute "checked" of checkbox
Try this to check
$('#captureImage').attr("checked",true).checkboxradio("refresh");
and uncheck
$('#captureImage').attr("checked",false).checkboxradio("refresh");
Try...
$("#captureAudio").prop('checked', false);
Both of these should work:
$("#captureImage").prop('checked', false);
AND/OR
$("#captureImage").removeAttr('checked');
... you can try both together.