jquery stop/pause jcarousel play whilst fancybox is active

Question

I have a jcarousel playing by default (ready function copied below). I also have a thumbnail image link on the same page which opens a fancyzoom overlay div (#flash_box) containing a video. I would like to stop/pause the jcarousel whilst the fancyzoom overlay is active. I'm sure this is possible, but I'm still struggling to get the fundamentals of controlling jquery elements like this. Any help much appreciated.

// Ride the carousel...
jQuery(document).ready(function() {
    jQuery("#mycarousel").jcarousel({
        scroll: 1,
        auto: 4, // delay between image slide
        wrap: 'last',
        initCallback: mycarousel_initCallback,
        // This tells jCarousel NOT to autobuild prev/next buttons
        buttonNextHTML: null,
        buttonPrevHTML: null,
        itemVisibleInCallback: {
            onAfterAnimation: function(c, o, i, s) {
            --i;
              jQuery('.jcarousel-control a').removeClass('active');
              jQuery('.jcarousel-control a:eq('+i+')').addClass('active');
            }
          }

    });
});

    $(document).ready(function() {
        $('div.photo a').fancyZoom({scaleImg: true, closeOnClick: true});
        $('#flash_box_link2').fancyZoom();

    });