Arrived to noisy outdoor unit Tested fan and compressor separately, compressor is the source of noise. Tightened compressor retaining bolts to ensure compressor was secure to the bottom of the unit. Placed gauges on equipment to attempt to determine the cause of the noise. Initially identified extremely low return air temperature, and found a faulty bypass damper that was allowing too much supplier to return directly to the system. Secured bypass closed and return temperature rose to normal. Once the bypass damper was closed and heat was allowed to get to the evaporator was able to determine that system was overcharged. Removed 2 lbs of r410 to see if the reduced workload on the compressor would quiet the compressor. No change was notes. Identified poor installation practices, system is physically too large for the space. The supply plenum is 6-8 inches tall with 14 inch ducts attached. The duct collars are so distorted and have been distorted and forced into an oval to attempt to ma