[Plugin: Ultimate FaceBook Fan Box] Not displaying correct number of fans

I have the Ultimate Facebook Fan Box plugin installed and have 9 likes on my Facebook page and have the plugin set to display 10 but it will only display 4.
Even if I change the plugin to display 5 fans it will still only ever display a max of 4.
Any idea why this is?

https://www.ads-software.com/extend/plugins/ultimate-facebook-fan-box/