evening all.
i have a very strange problem im trying to work out,

i5 desktop, win 8.1 gtx660 card 8 gig ram

ok so, sometimes when i play a game , mouse works etc , but no keyboard input controls work , upon exiting the game checking in notepad the keys are working . this is happening across origin games and steam so its a broad problem wondering what can be causing this , as when this happens i reset the PC and all is normal again. what program conflicts could cause this? i use kaspersky total security, i read somewhere of someone else having similar issues and it was a form of service inside of that AV .

any ideas would be great .

cheers