The channels feature will show actual posts an admin has made to the Facebook page. Looking at your Facebook Page, all the posts since August 7th have been "shares" of other content. Currently, we don't display shares as the data that comes back from Facebook to represent a share isn't always complete and there usually aren't comments that go along with a share, which makes the promotion of it on user's site (generally) less valuable.
That's not to say we're right, but I'm explaining what we currently do. If you feel that shares absolutely should be shown in the feed, please let us know and we can investigate further. For now though, I'd recommend creating more content on your Facebook Page and verifying that it displays as expected.
I hope that helps,
Alex