Some of the numpad keys do not work

There seems to be an issue where, on the numpad, some of the keys work as their alternative.

I.e. 5, 0, /, *, -, +, and ⏎ work as expected (with NumLock enabled);
1 works as End
2 works as ↓
3 works as PgDn
4 works as ←
6 works as →
7 works as Home
8 works as ↑
9 works as PgUp