I have a 2021 Uforce 600 with the full cab and hard doors. The noise level inside is absolutely ridiculous to where you have to yell almost scream to talk. I have installed two layers of sound deadening material on the floors, kickboard, completely behind the seats, the storage boxes, and the roof. I even installed an overhead stereo which I cannot hear when I'm driving my 600. I'm at a loss on what to do now. My next move I'm thinking is to install sound deadening material on the rear poly window because it sounds like some of the noise is coming from it but it's not vibrating to the touch when I drive. I've also bought an exhaust pipe silencer to try to see if that helps. I know it's transient vibration that is flowing through something but cannot figure out where. Anyone have any ideas? Thank you