Found the issue and it's neither an OS nor keyboard driver issue. Turns out the way you put the Asus S400CA into num lock mode is fn (second key from bottom left) + num lk (2nd key from top right). Probably other laptops as well. Somehow I hit those 2 by accident, maybe by closing the lid. Num lock mode turns some of the keys into a number pad like you'd have on a big keyboard, as a result, j=1, k=2, l=3, etc. If you ask me, this is a strange feature.
I plugged in my Microsoft Wireless Keyboard 5000 into a new Asus S400CA ultrabook. However, some of the keys on the laptop keyboard itself have been remapped. For example, pressing 'j' gives me a '1' and pressing 'i' gives me a '5'. The problem remains even when I unplug the wireless keyboard.
Can anyone help me figure out where the root of the problem is? Is it the wireless keyboard driver? The Asus keyboard driver? Something else?
I have the laptop dual booting to Windows 8 and Ubuntu 12.10 and the same problem exists in both OS's so it's making me think the issue is somehow related to either an older driver used by the wireless keyboard or something with the Asus driver...?
Thanks for your help.