Came out to call for a system making noise. We were out recently to check the system out because of the same noise and stated that it was a filter. I checked the unit over and found the lineset in the wall is causing the noise due to vibration of the outdoor unit. The system was also very low on refrigerant, so system does have a leak. I did an inspection of the system and the evaporator coil is in rough shape. Discussed with customer about options and repair vs replace. Customer wanted to wait on making any decisions at this time. I will send over all estimates to customers email.