Since installing macOS Sierra my right alt key is being mapped to ctrl. This behaviour is also visible on the keyboard viewer, where pressing the left alt key clearly activates the alt functionality, but pressing the right alt key activates the ctrl functionality.
How can i change this back?
I am using a Swiss German keyboard, but the problem is present in all keyboard settings. The problem must be computer-specific, since i do not have the issue when using the same keyboard on another computer with the same settings.
The device is an iMac 21.5-inch, late 2013 (i7)
Thanks for your help