Mk3 supra rear end noise

[combatantsomeone]

hey all
I got a mk3 supra with the factory lsd. I had a diff shop change the diff gears from 4.5 to 4.1. Car now makes a sort of a fast knocking sort of noise that appears to come from the rear end. This occurs mostly at higher speeds 80-100km/h and only occurs on deceleration/coasting. There is only a slight high pitched whine type noise under acceleration and no noise when cruising.
I think its the diff but the shop that put it together thinks its a wheel bearing?
Has anyone got any idea what it might be?
Any help greatly appreciated

[pandaah]

Let the guy from the diff shop have a listen

[combatantsomeone]

I took them for a ride in the car, was a bit difficult to hear coz of twin walbros buzzing, but he still thought it was a wheel bearing

[combatantsomeone]

UPDATE
jacked the car up today and ran it with the wheels off the ground
Left wheel does NOT spin at all, forward or back
Right wheel spins