As far as associating this phenomena with anything beyond another person, if you can "sight hear" say an animal or better yet an audio speaker reproducing sound, now that there is something I would pay to witness. Being a little hard of hearing, early on I found I could understand speech better when I was watching the person speak in order to lip read even when I did not realize I was doing it. We know the movement of the mouth and lips to produce sound and automatically use it when watching others talk.
Don