Ad-Sharing not showing on posts on single install, but shows on pages

I have installed Ad-Sharing on my single install WordPress site. I have inserted the ad code but it is not working on posts, yet works on pages. Even changing to just plain text (such as ‘test’:wink: still just shows nothing on posts.

Here is a link to a post (ads should be showing both before and after post)

http://anti-grav.net/2012/11/cities-in-motion-london-announced/

Here is a link to a page (ads are showing with no problems)

http://anti-grav.net/jobs/

I have tried uninstalling the plugin, re-installing, removing other plugins in an attempt to get it to work, but nothing seems to be clashing with it.