I'm having exactly the same problem as you when using my Logitech wireless touch keyboard K400r.
It ran without a glitch at my WinXP Intel desktop PC but with the received in the front USB port of NUC, the jittery mouse pointer would not respond when keyboard is anything further than 2 feet away from receiver. Very disappointed with the NUC, cos I wanted to mount it behind my LED TV. If wireless I/O can't be used, then the purpose of NUC is gone for me.