Pittsfield, MA — The production of “Noises Off” at Barrington Stage Company is an impressive technical achievement that frequently adds to the abundant comedy that is in the script. Director Gordon Greenberg’s slapstick approach is gloriously performed by a game, tireless and inventive cast. The actors give their all, especially in the physical aspects of the work. It appears so exhausting you wonder how they can ever do two performances in a si…