Idling with AC on, I hear a noise come and go periodically. Some sort of eww sounding noise. Higher pitch then a low hum like a suction leaking noise maybe. No air leaking pssss or type. It cycles some. Maybe compressor or AC related?
have you noticed a lack of cooling? Mine made a simular noise and it turned out that my condensor was leaking the freon so I took it in and had it replaced. Problem solved.