Mouse input lag/stutter makes game unplayable

When i press w to move forward, there is a delay.  When i release W, the character continues running for a short, but random amount of time it seems.  If i move in any direction, the same thing happens, back, strafing, etc.  When i press g to bring up my grenade, the animation starts, hands come out, then suddenly snap back and im holding my primary weapon again.  Mashing g usually gets the grenade up after multiple attempts.  There is mouse, and keyboard movement delay on everything i have tried, every setting, etc..  I have never had this issue with any other game, including recent titles like Vanguard, Forza 5, etc..  I literally cannot play a game i spent $100 on, and i cant seem to find any help online.