"Stop making noise" is far more commonly used. You would only use "stop making a noise" if you were talking about a specific noise, and even then you would probably say, "Stop making that noise". For example, if my son is tapping his fingers on the table and the sound bothers me, I might say, "Stop making that noise.' But if I'm on the phone and my children are playing and just generally being noisy, playing or talking or whatever, I would say,"Stop making noise."

Stop making a noise is correct one my friend . It depends on the context