Well I logged in 4 times to answer this,
Are you using IE for your browser? If so that's a common issue with IE & our forum software. A work around if you're married to IE is to uncheck the remember me box when you log in. Some report that they stay logged in as long as their session is active. Those with FireFox or Chrome browsers don't have that issue. There are a few threads in the Shortbus about that issue.
