Shortcut for Back View (Ctrl 1) doesn't work This is really strange.

When I press Ctrl1 the view should switch to Back View, according to my preferences.



It's even listed correctly in the menu:

 

It doesn't do anything.

Ctrl3 for Left View is working, and Ctrl7 for Bottom View is also working.

I use Emulate Numpad as a standard always, even on machines where a numpad keyboard is available.

My OS is macOS Sierra. Blender version is 2.79.

The most bizarre thing is that it still doesn't work even after I Load Factory Settings (and re-enable Emulate Numpad). This makes me think it might not be my settings at all. (Possible bug?)

My Ctrl key and my 1 key are working just fine for all other uses, in Blender and in other apps.

It's really a hindrance when modeling. Any ideas? 

Thanks.
The macOS Japanese text input implementation was interfering. By disabling it and using the Google IME instead I was able to regain normal functionality of my Ctrl key.

Anyone wanting to know more can read the question I posted on Ask Different that led to solving the mystery.