The address bar doesn't change the URL during a 301 redirection.
For instance in Firefox, type in "amazon.com" and that address remains in the address bar when you arrive at the amazon site. Try this in another browser (IE) and the address changes to "http://www.amazon.com". It does the same thing for any web site when you type in an address without the www. in the URL. How can I enable Firefox to display the complete redirected URL?
This is how it worked for me: After disabling all my add-ons that problem was gone. I gradually enabled all the add-ons again to see which one was causing the problem
Disabled AwesomeBar HD 14, problem gone.