Back in 2000 Newmar offered the Powertech as standard with the Onan as an option. The first Powertechs (as optioned by Newmar) did NOT have the QUIET insulation package offered by Powertech. So, the originals were louder than Onan's and the Powertechs with the Quiet insulation package. A few years later, Newmar used the Powertech's with the quiet insulation package. That said, once the APU has run for awhile and warmed up, they tend to quiet down a bit. So, run the APU for at least 30 minutes and see if it does not quiet down some. Doug