I've been experiencing a problem with my keyboards lately. I own an Alienware laptop M11x. I've attached a USB Trust keyboard first and experienced some problems while playing FIFA 12. Namely: When the Left and Up buttons are pressed I cannot press one of the buttons S, G, B, N, H. S is very important since it's my pass button.
So I took the keyboard back and bought a Microsoft Keyboard 600. Alas, the problem still persists. I must say that for instance I can press 4 buttons like: A S D F and it will work like a charm.
Update: I must say that that particular problematic combination works on my laptop keyboard and it persists over the whole system.