v2004 is pretty old so I can't say what it could be--I don;t recall any issues like that when it was an active version so it may be an interaction with some other (newer?) software or hardware. So we can at least rule that out--could you download and install the latest version on one of your machines and see if that resolves it? We can give you a code to test it out for a few weeks. If that's not it, we can explore possibly updating your video codecs.