Any way you can disable AVG completely (temporarily) to see if this is causing your issues?
May not be AVG but it's worth a try.
Also: Try with only one monitor connected without any other hardware plugged into USB slots (other than M/Keyboard).
Edit: And is it my understanding that no other game has this lagging issue?
Edited by bludgard, 19 December 2016 - 05:36 PM.