Embed Bug?

Howdy. I’m have a lot of problems with embed code lately. I am super-admin for my site and don’t seem to have any problems putting in YouTube or, in this case, a flickr slideshow. But whenever people at the contributor level try to insert embed/object code it just dissapears when they save the post – literally “poof”!

What is wrong with my set up that keeps causing this? It’s incredibly annyone to have to get all these emails from people and insert their code for them….