Let let me tell you a little story, we replaced the two piece with a one piece driveshaft in my truck, new universals installed by a machine shop.
past couple months I've had a chirping noise in the back like you're describing, also the truck has had a shake at 35 55 65 mph had me convinced the rear end with shot. took it to a shop confirm what I was already pretty sure of. ?
They dropped the shaft off the back flange cleaned the flange of rust, greased the new universals, put it back up, started& ran it at high speed with the wheels spinning while on the lift. he put a pencil against it and showed how it was running very very smooth and not making the chirping noises anymore he also showed me which was pretty obvious that both of the nearly new tires had flat spots on them,. new tires no more shake no more chirp! ?