I noticed on our 213 the pump is only noisy if there is air in the lines.
When I fill the tank I turn on the pump and then I pull the 2 low drain shutoff valves for about 5 seconds. This purges out any air in the system. The pump is then super quiet. i have no insulation around my pump.
Before I figured this out, my water lines would rattle due to the pumps vibrations.
2010 Jayco JayFeather 213 EXP
2016 Ford F-150, 4x4, 3.5L ECOBOOST, MaxTow, Supercrew, 6.5FT, 3.55 axle