Niva noise

The Niva calls again. I noticed this just now, I can hear a weird noise which sounds like a worn bearing starting at 30kmh (probably because the car is so loud while driving faster) and stopping at around 10kmh if I just roll in idle to a stop light.

Revving in Idle shows no sound so I dont think its the transmission. It sounds like comming from the rear

Wheel bearing? Diff? Cardan shaft?

Whats the best way to diagnose its origin?

Thanks