So . . . I will probably tick some folks off. I do not mean this disrespectfully, but if you want quite, get a jeep. I have 2 and love them for rock crawling, but they beat you to death on the trail when driving, however I also have a Can Am x3 turbo rr 4 seater (pictured left) that fly's down the trail, and is much noisier than my Northstar.
I have the ADV5, and maybe because its a 4 seater, the noise level is substantially less than my Can Am, and to me is not annoying at all. It is part of the cost of having fun in these machine's.
As I said, if you want quiet with a comfortable conversation, then you should go the jeep route, if you want to have a fast, marshmallow smooth ride down the trail, go Polaris (or Can Am) and accept the price of admission.
Just my 2 cents (now twenty bucks due to Bidenomics) worth.