I think most Class C motor homes make squeaks and rattles. The joint between the cab and overhead box seems to be a significant source. On mine, it has not been loud enough or consistent enough to be annoying, or to force us to speak above a normal conversational tone. There are a few rattles in the back, too. But again, not loud enough to worry about. I did put a new latch on the bedroom closet door, as we determined it was sliding and slamming. And I put some Velcro on the toilet brush bucket so it won't fall over while traveling and slam to the floor. Aside from that, the whistle of the turbocharger is the main thing I hear.
2006 Jayco Seneca 34SS
2006 Jeep Wrangler Unlimited Rubicon Toad