It sounds strange to me.
cursors or home/end ( and others ) on alpha keys work in Numlocked mode using in combination with Shift key.
I would like to know how you get cursor function to left with "U" key.
If your BIOS set to Num Lock on upon system boot. ( this might be default selection ) ,
then Windows automatically set your mini M in Num lock mode. You will get "4" typing "u" key.
So normally, you need to press Shift/Numlock to set your alpha keys for normal usage to get "u", "i", "o" as printed on key caps.
Pressing Shift/Numlock let the num block in the alpha keys to Num lock mode.
Now you will get 4,5,6 from U,I,O keys respectively.
to move cursor left direction, you have to press Shift/U. In the Numlock mode, Caps lock
doesn't wotk as shift function for those double assigned keys ( num block in the alpha keys).
At least mine works as above.
But why you want to get numbers or cursor function by using alpha keys?
Numbers are already there below function keys, page up/down, home/end and cursors are ready to use without pressing Shift/Numlock.
Am I reading your comment wrong?
If you typed your comment with mini, then your Shift keys should be OK because you wrote comment in combination of Caps and small letters.
But if not, check your board if you can get small letters or not. It seems like your Shift key is permanently on no matter if it get pressed or not.