Just to update. I seem to be getting the same problem again but it appears the issue is my browser.
When I attempt to logon from a different browser the issue does not appear.
However, when I attempt to log out of from stackideas.com on the affected browser I get the error "invalid token" and the issue persists when attempting to log back in.
Is this perhaps an issue with Joomla that causes this for some browser sessions? Just curious, not a high priority but I know some users have been experiencing issues with EasySocial and user logons.