Bluetooth Keyboard - Wrong Keymap
The issue is due to Numlock activating, resulting in part of the map being interpreted as a numeric keypad, and the rest doing nothing. At least with Apple compatible keyboards, the solution is to press Fn+F6 a couple of times to toggle Numlock off. You should also look into editing /etc/numlockx to disable Numlock by default. There is also a Gnome or X tweak mentioned at Apple Keyboard – Numlock on Apple Wireless Keyboard.