Audio problem: When RoboCop is being tested in the shooting gallery, he puts his gun away in his leg. But the sound effects for his leg closing are out of sync with the actual movements of his leg. (00:32:55)
Audio problem: At the end of the movie where Dick Jones is falling from the OCP building. At the end of the shot you can hear the splat sound. But he's not near the ground yet. He is still seen up in the air. (01:36:00)
Answer: When Bob Morton is told by a tech that one of Murphy's arm was saved, Bob stated that he wants total body prosthesis. Meaning Robocop's entire body was synthetic. None of his actual body was used. The only thing that was used was Murphy's actual face.
Also, his human brain, and possibly his spine, where OCP could wire him into the suit.
Movie Nut