I have a client who is experiencing odd behavior with her NumLock key that I can't figure out.

The computer is an Optiplex 7010 Micro Plus with a wireless keyboard/mouse combo KB3121Wt. The BIOS is set to turn NumLock on by default when the computer powers on, however, when she gets to the login screen, she has to press the key again for NumLock to work. Dell Peripheral Manager is installed, and there's no options to configure the NumLock that I could see in there. I know the indicator light on this keyboard turns off even though NumLock itself is still on, but that's not the issue. After using the number pad just fine, she can logoff and again when typing her password in, the NumLock will be off. The light turning itself off only adds to her confusion.

Any ideas? Is this a setting in Windows somewhere maybe?