Input lag/freeze on PC

Hi everyone! Since the last patch (1.4.0) the game is unplayable. 
The controls stops working for some seconds (in online games and also in UT menus while change tabs). 
The game still continue with no lag, the connection is stable but the inputs are not registered.
I tried to change framerate or frequency and turn on and off vsync but nothing change.
Someone has any idea how to solve? Thank you in advance.