There is a div with id "fb-root" that we put on the page to add the Facebook javascript and initialization. For some reason, it actually looks like JomSocial is setting a margin on JFBConnect's div. In /components/com_community/templates/jomsocial/assets/css/style.css around line 2926, they are setting a margin-top of 8.65248px. This is your problem.
-Melissa