Hi, I have a canon rebel xs and bought the canon 430exII speedlite in November. It's been working great. I take nightlife photography, and it's been awesome. Faces are a good tone and come out perfectly lit. In the past few weeks I've had a huuuge problem with my flash. The batteries are fine-I've tried with putting new ones in. The first few pictures will turn out ok, then suddenly the pictures will be incredibly overexposed. Almost a total white out. So I take the flash off and put it back on, and everything's fine. This happens at least 2-3 times a night. I'm not changing any settings. The flash is pushed the whole way into the shoe also. Can someone please help me?? Is it settings that are getting screwed up? Has this happened to anyone else?