Problem (see details here):

When we test a Flash movie in a web page, the SWF may be cached by the browser software, so that when we make modifications to the SWF, the browser may continue to display the cached version of the SWF and ignore any new version.

Solution:

adding a time stamp new Date().getTime(), thereby force refresh from browser every time:

embedpano({
    swf: "xx.swf?_t=" + new Date().getTime(),
    xml: "xx.xml",
    target: "pano",
    html5: "prefer",
    bgcolor:"#323232",
    passQueryParameters: true
});

It’s said that methods as such don’t work in IE7, and if you want it dealt with, check out AS solutions in the link above.