Did you accidentally hit the bracket button on the changing ISO camera and turn it on? A similar event happened to me and I didn't realize I had auto bracketing on.
jerryc41 wrote:
I think I did that, but I'm wondering if there's some obscure setting I may have missed. This doesn't seem like a defect, and the ISO button isn't sticking. I did the two-button reset. When I turn the dial on Camera A, the display remains in the top LCD. When I press the ISO button, the rest of the display goes away, and only ISO is displayed, as it does in Camera B.