Rotational Whoop Whoop

Having searched the threads thinking it was my viscous coupling on the blink I think my issue may be different.

At lowish speeds normally when turning sharply in either direction or in a carpark for example, I hear what can only be described as a whoop whoop, a slow muffled machine gun sound emanating from the rear floor, some sort of rotational distress.

Anyone any ideas or is my description pants???

pants ,check prop suport brgs,diff brgs

my guess is prop bearings as that noise on mine was cured after new bearings.
second possibility is diff bearing-check for play in diff nose bearing by rocking the rear prop up and down