I read on another forum that someone had the same type of noise from their a/c and he went on the roof and found that some of the screws around the fan motor shroud and compressor were loose. He tightened the screws and most of the noise went away. So far as the shaking goes, I had the same problem with my l/r ac. Dometic sent some softer rubber grommets for the compressor which took care of the problem.
Don