Larry, I would contact Scamp
or Dometic directly. If it's bothering you, it's possible others have complained too. The Coleman Mach 8 on our Casita
had an exterior noise issue and Coleman/AirExcel came out with a modified fan that helped but did not eliminate the issue. I've heard that they've made some further changes since then.
An outside vendor came up with a solution that fixed the exterior noise issue. We then found, like Casita
Greg, the biggest problem for us was that when the compressor kicked on, it literally caused the trailer to shake. We also installed the EasyStart kit and it made a huge difference.
Part of the issue is that these are small trailers with very large air conditioners, and you are sleeping right under it. Don't rule out earplugs.