Unfortunately, I don't know either. Something is obviously doing it. My guess would be a plugin (check system plugins as well as other groups), but it could be something like an improper redirect in an .htaccess file or a redirection to a page that is somehow registered, which Joomla would then redirect back to the home page.
I really don't know your site, so I can't give you a more specific answer or solution. Since it's something that's not directly related to JFBConnect and more underlying with Joomla itself on your site, it's difficult for us to diagnose.
I hope the above helps narrow things down though. If you need anything else, please let us know.
Thanks,
Alex