ANSWER: Compressor not properly installed on concrete slab.
A new layer of asphalt was installed around the AC compressor, and the compressor itself is set in the asphalt. This reduces the efficiency of the compressor by blocking a portion of the surface area of the coils. This also makes it rather difficult to replace the compressor. All exterior AC compressors should be installed on individual level concrete pads for maximum efficiency and longevity.