With no other reports of this happening, thinking it might be a setting in you computer/browser doing it.
What browser are you using? I use IE7 (Crome occasionaly) and have never had it happen.
If you are using IE, look in your tools (internet otions) menu and go to the settings of your browsing history. You want it set to always check for updates or automaticaly. Attachment below is a screen shot with that menu open:
View attachment 8
If that all looks OK, i would suggest what Radtex mentioned (think that is how it is worded in Chrome?) OR go in and delete your browsing history in your tools menu. Delete the temp files, cookies and history. Thinking it could be a hang up in how your cookie is reading....