posts not showing up in category pages

Since I updated the Membership plugin to 3.5.2 (and 3.5.2.1), posts are not showing up in my category pages. For example, see: http://clinspirity.com/category/blogs/the-empa-site/. There are about 10 posts in this category that should be showing up. If I deactivate the Membership plugin, they all show up.