Originally Posted by A Traveller
The way web pages work, if your session times out due to inactivity, of course it still says Sign Out in the left hand upper corner.
That is because that was the state of affairs when the page was last retrieved from the server, but then later the server thinks you've been gone for too long and invalidates your last login. Your web page on your computer doesn't change as a result of the server's decision.
Try clicking on the refresh button of your browser (or F5 in IE) to see what happens after you've had a period of inactivity. That should refresh the logged-in indications on your web page. (With an emphasis on should.)
Your explanation does not appear to be what's happening here. Just going from one part of the site to another after first signing in causes the problem. Session timing out does not appear to be the problem, unless the timing out happens in 30 seconds or so.