the pipe that goes from the drum to the pump has a ping pong sized ball in it,

My question is, is this ball supposed to be in the pipe itself, or between the drum and the pipe?
As recently our washing machine has started leaking from this pipe, i have took the pipe off and inspected it finding no cuts or cracks in the pipe, but thought it odd to have the ball actually in the pipe itself

Any advise welcome thanx paul

crazy diamond, December 2010