Since I upgraded my MBPr to MacOS Sierra, two keys seems to have been switched around in the keyboard when I use my external keyboard.
I use the Spanish-ISO layout, and the "º" and "<" keys have been swapped. The laptop's keyboard works fine. I have not fiddled with the keyboard configuration, other than changing to my regional layout and swapping modifier keys (it's a windows keyboard).
It worked flawlessly1 before the upgrade. I know very little of how to troubleshoot MacOS, what should I do?
1 I just remembered that, no, it wasn't all that flawless; from time to time the keyboard would stop responding, and I'd have to unplug and plug again. Don't think it's related, but...