This is normally caused by there being allot of payers in the "area" and can cause allot of lag/FPS drop this happen to all of us just depending on the Spec of your computer/laptop some players will be effected more than others, at the moment in time there isn't much you can do to resolve this unless you're prepaired to upgrade your computer/laptop or you can wait and see if a MP update fixes this for you
Regards
Gareth