SL280 Engine Whine

[liammc]

This whine has been becoming more apparent over the last couple of months. It only happens when accelerating hard and increases with engine speed. When pulling hard from standstill it is now as loud as the engine itself. The car has recently been in the dealership for other issues and they mentioned that the belt will need changed sometime soon.

Is this the likely cause of the noise or are there any other possibilities.

Thanks