I would like to make a change to my AC units so they are not so noisey. I have heard that the noise comes from obstructions in the air flow. I have also heard of people redoing the ceiling vents so ...
You may have to get a Newmar to get quiet AC. When we had a couple of Fleetwood units (Pace Arrow) the TV or talking would have to be loud to hear above the AC noise. The Newmar is so quiet you have to check if it is running when on low speed.