Yep it's definitely an issue with my keyboard, same behavior with this test application, thanks for pointing it!
raidho36 wrote:The to-go solution that avoids all possible problems with input, literally every single one of them, is having input customizable.
Well actually it's while I was implementing it that I noticed this problem, so yep a solution for someone experiencing this issue too is clearly to map his inputs differently, and anyway someone using the KP keys to move the character won't use shift to run (as the mouse is needed too), it will probably be mapped to another KP key.