Customer stated noise from outdoor unit on shut down. Checked charges and Amp RLA Found no problems with system. Noise is system Ramping down through speeds to shut off and EXV Equalization. Waited for system to cycle down to off to try an determine what noise is. After waiting for system to finally shut off i found. On shut down compressor makes a sudden stop that causes noise. Pressure were at 160/309 when system shut down. At 7.5° sub-cool at point of shut down. System working within factory specifications. Noise at sut down is the thing that needs looked into equalizer or something else that is not allowing for a smooth shut down Looking into the answer and will get back to customer when we have proper answers. Could be a multitude of things but acts as if it shuts down under load.