BisVal said:
I had the same problem with my fresh installed Win 7 Ult 64-bit on a PC. I thought the problem was the keyboard or the mouse , changed them , but the problem was still there. Finally run Malwarebytes and it found a rootkit - it was deleted and the problem was solved.
Huh. I thought it was that so I ran MWB and it found one. Haven't restarted though. If this is the fix I feel like an idiot.