This is a typical application for the "history hack". You can append a hash "#" value to the end of the current location URL. This will not force the browser to reload the page (as it does after any other change to the location URL), it is bookmarkable and it will be stored in the browser history.
Code:
// on page load check the hash in the URL and execute the respective AJAX function
if(window.location.hash) {
ajaxpage('/staff/_frontend/listen_record.php', window.location.hash.substring(1)); // substring will cut off the leading #
}
// later on in the page, after changing the content and using the ajaxpage() function, you'll have to change the hash
var newcontent = 'about'; // example
window.location.hash = newcontent;
Some of the newest browser versions support the History API ... but not all of them yet.