I have a '21 two door Rubicon and I can honestly say I've never heard that noise.
Take it back to the dealer and let them have a go. it sounds like something is loose or there is a bushing missing.
Ok, AOAA now has two badge trails. Rousch Creek has three badge trails. They are about 45 minutes apart. Country Inn & Suites in Frackville Pa. has a discount if you tell them you're in town for off roading.(about 35 minutes from AOAA) Peter Mills is a nice gravel road.