Upon arrival homeowner stated that the system would make a thump sound when shutting off. Turned system on and checked outdoor unit. Turned system off at the contactor and disconnect 5 times each and could not get the system to make the noise. Let system run for 10min and then tried to shut it off again but no sound. Had homeowner outside and couldn’t get the system to recreate the issue. Checked capacitors and hard start all looked good. Explained to homeowner that if it happens again let us know and try to record the sound.