I can see where you probably got confused with my posts, and I really should have explained it a little better. For this I apologize. To clarify, it doesn't happen every time I pull the trigger, but it does happen at least a few times with every trip to the range. I have tried field stripping it and couldn't find any visible problems with it, and yesterday when I went to the range I made it a point to pay attention to my thumbs so maybe it wouldn't happen. It still did it one time at the range during a rapid fire string. I agree with what most people are telling me about my thumb hitting it and I guess that it gives me another reason to go to the range and practice more.
I did have almost the same problem with my Springfield XD except on it I was pushing the slide lock down and it wouldn't lock back on empty. But anyway like I said I apologize for the confusion.