one of our members is now having the same problem I am. The are using Firefox like I do.
He too has always set his views in PP side of our website to 90pp. Whenever he logs out and comes back to the website, it no longer remembers his 90 pp. Its still happening to me as well. I clear out all my cookies, and it works for a day or 2, then I can no longer sort or change the photos per page. I can't keep clearing out my cookies every 2 days, that messes me up with other websites.