Note to Hamlet, 2.2.332-333: "I think their inhibition comes by the means of the late innovation."

inhibition: hindrance [to playing in the city].  late innovation: recent vogue. The word "inhibition" could also mean "official prohibition"; and "innovation" was sometimes used by Shakespeare to mean "political uprising or revolt," so it's possible that Shakespeare is alluding to an official prohibition issued against a theatrical company because of some disturbance associated with a performance. However, it's more likely that Shakespeare is alluding to the vogue for boy actors which arose in London about the time Hamlet was first performed, and which is reflected in the speeches of Rosencrantz, beginning at line 339. This episode in English theatrical history is connected with the "War of the Theatres."