Any ideas? I've tried and tried to use this flash on eTTL and it will consistently overexpose (though how much overexposed varies). I cut two index cards and taped them over to act as a diffuser, helped, but still overexposed (and for some reason bouncing this flash makes it overexpose worse). I then bought an Omni Bounce Diffuser hoping that it would solve my problem...WRONG. It actually overexposes even more now (again, especially when bounced). I've even tried using their built-in diffuser, but that just makes it worse, because when you flip the diffuser down, it brings the light closer to the diffuser, so it overexposes worse than without anything over it. I feel like I was ripped off as I paid ~$150 for a flash that overexposes. Any ideas? Do you think it's a defective unit? I just don't know what to do with this thing. I'm considering selling it and getting a Canon 430EX flash.