I ran in to this problem so I am sure, at sometime, you may also. I had what seemed like extra, blank, movie at the end of on of my projects. When I looked, I noticed it even showed up in the main viewer and also showed up the clip view (see arrows).
I switched from clip view to the timeline view, scrolled the movie all the way to the right, then zoomed in a bit. What do you know? A little piece of audio hidden at the very end of the movie (see arrow)