Wheel bearings, rear diff, ebrake or brakes. It's hard to tell in the vid with the radio on. Best thing to do is put the rear on jack stands and disco the drive shaft. Chock the front wheels, release the e-brake and spin the tires and shake the tires up and down, left and right. There should be no movement up and down left or right. See if you can hear the noise either coming from the wheel end or if it's in the diff. Take the tires off, inspect the brakes, take the rotors off and check the e-brake for broken material scraping around. Check the pinon for up and down left and right movement. If you still can't find it, take the diff cover off and drain the fluid. Check for metal shavings and inspect the gears as you spin the tires.