Paul,

I wouldn't worry about the Liberty aux air compressor. The one in Gary's Liberty came on during Jon's leveling system seminar and the whole coach started shaking like a dog crapping a peach seed, so I think it must be normal.

The Royale was not quite that noisy, but the Marathon compressor is located in the generator bay, so I could hear a mosquito buzz all the way over at the Krakman's coach when it was on.

Or at least I thought it was a mosquito....