Quoted from DaveH:

I've also had several games with them. Even my AC/DC Vault has them, and I've never had a single issue with them until GZ. And then I looked around and lots of people are complaining about them in the latest runs. They simply have a bad batch of them, and come to find out Stern doesn't even test if a game can go into the menus when they finish assembling it... Because there is no way that isn't noticed if someone had gone into the menu.
It's a standard QC issue. Bad set of parts that were not checked before installation, and the final product was not checked before shipping them to customers.