I had a similar issue with my 2014 Palazzo. I found that the water pump, located in the bin next to the water tank, was clammering against an adjacent metal wall in the storage compartment. I rammed a piece of hard foam into the gap between the pump and the wall. The pump is now much quieter.
Look on Amazon for a water pump silencing kit and accumulator, installing both will make a difference in noise level and water surging. Get a thick piece of scrap carpet and place under the pump. Also placing a cheap styrofoam cooler over the pump helps, you may have to cut it a little to fit.
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FMCA 101070S Dave & Myra One day your life will flash before your eyes,
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I added an accumulator during a trip, where I didn't have much for tools. It mounted with the original piping, but now just has one screw into the floor instead of 4. It did make the pump quieter, but more important for me was that it reduced the pulsing that was annoying in the shower.
It was an easy DIY project. Just be sure you check for leaks when you are done.
Bad decisions make great stories!