This javascript function seems to be the cause of the loop problem. Any ideas on modification of this code or an alternate css / html approach to full size iframes?
$(function(){
if($.colorbox) {
        $('.lightbox').filter(':not([href*=lightbox\\=0])').colorbox({iframe:true, width:"100%", height:"100%"});
        $('svg .lightbox').on(clickEv, function(){
            $.colorbox({iframe:true, width:"100%", height:"100%", href:$(this).attr('xlink:href')});
            return false;
        });
        $('.thumb').colorbox({maxWidth:"95%", maxHeight:"95%"});
    }
});