Things are posting in multiple??

For some reason, all of a sudden, some of my posts are multiplying themselves. When I look under Manage / Posts they’re only there once but they’re showing up 2-4 times each on the blog. I’ve tried different templates to see if that helps, which it didn’t (this occurred yesterday when I was putting up a new template) and I’ve tried erasing the post and re-doing them and they reposted in multiples again. Has anyone ever heard of this? The only other thing I’ve changed is adding a category visibility plugin.

Thanks in advance for your help.
Meg
http://megsmind.com