Ticking Noise [ENGINE] only when Reversing

Ok People,

I have a ticking Noise coming from under the hood when the car is reversing. It does not make any noise when I'm turning fully Left or Right from start-off. I have no engine noise when going forward and I have no noise at all from the gearbox.

Regards,

It only happens when the car is moving in reverse and I have no noise going into or out of reverse

It like

TickTickTickTickTickTickTickTickTickTickTickTickTickTickTickTickTickTick

Unusual, what car is it?

It is a Subaru Wagon 2000. This noise does no occur when reversing really slowly it really sounds like something tapping off something. I will put some photos of the car up soon!