re: t3i "Movie recording has been stopped automatically"

Sounds to me like either the card went bad or the connections to the card are not up to par. Unfortunately, the only real way to test this is with another SD card. If it happens with the second card, the problem is in the camera; if not, the problem is with the first card.

But in every case I've ever seen or heard of, that message is caused by the camera's buffer filling up, which in turn is caused by one of the two situations above.

HTH - Mark