I should look into the firmware…. however, I received bad news.
That photog called me yesterday after fixing and inspecting my camera. He said yes in fact one of the tabs that holds the focusing screen in place was broken and he replaced it. However, when he tested it, he noticed something weird- after locking focus, he could hear/feel the focusing motor continuing to run! He first tried out his other 5D Mark IIs and they didn’t do that. He said he called up his friend who works at Canon (of course he has a friend who works at Canon… lol). The guy basically told him it is a rare but known problem with the entire AF system, and when a camera arrives there for servicing and is under warranty, they send the customer a whole new camera. Wow. Not what I wanted to hear. He said what happens is the vertical and horizontal electronic focusing mechanisms become out of sync, and it’s not repairable. (well, not for less than maybe $1000). So- basically it will work, but it will be inconsistent. I’ll still have to shoot multiple images to ensure some are in proper focus. He did say it was more pronounced with the broken focusing screen, and discovered also using the back button focus and pressing it about three times before depressing the shutter the rest of the way seemed to help a lot. The worse news is that the problem could get worse and could just stop working altogether. I need to buy a new camera. I’m also ticked because I think this problem might have been there since I bought it and potentially the seller knew there was a problem and didn’t disclose it. I have two backup bodies but neither are really suitable for portrait sessions and they are crops, while my main lens is a 70-200 f/2.8. With good lenses they are ok but don’t shoot high ISO well. And neither are wedding cameras, so if I 2nd shoot any weddings I would have to be supplied a camera.