T3I Fading to black while shooting

[Herdie]

Okay I've been having this problem for a while now and I can't figure out why it is doing it. The subject line says it all, the video fades to and from black while shooting. Here's a sample on one of my takes. https://drive.google.com/file/d/0B4-HdPKDkd2QMmxid29OU2dXMlU/edit?usp=sharing