Sorry to butt in, but I recently read this in my Ball Python care book. The author said he had a python that was acting aggressive, and they finally realized that because his cage was in the laundry room, and they had just gotten a dryer, that it was vibrating his cage. They moved him into another room and he calmed down and stopped striking. The point of the story was that there can be a strange, but very real reason for the change in your snakes behavior.

I hope someone who is an expert can help you out more!