I was testing the video functionality by adding a junk FLV media file to one of our studies. (The Video button showed up both in the Studies List and in the Study.) When I was done, I unpublished it.

When I did that, the Video button properly disappeared from the Studies List. But it was still there in the Study view! I had to unlink the media file from the study in order to get rid of it.

There may be a problem with the model of the studyview - we'll check it out.