Online list "sort" not working correctly ?

When looking at the online list, it seems fine, but when I click on the "forum location" tab to sort the list, it looks like users are changing pages, but they are not.. 

For example Icky.. changes from index page to Replying.. now if I refresh the list nothing changes, but each time I click the "forum location" tab to sort, the index/reply changes each time. So I think something isn't sorting in the correct order in the list..