Power steering problem???

Right guys what could this be?? Had the Landy in the garage today for what i and a few other people off here thought could be CV Joints.Had a knocking noise coming from the front end when on full lock at slow speed and i like a few more thought CV Joints (anyway).The guy at the garage(my mate by the way) rang me and said he had found something under the bonnet?.The flexi pipe on the power steering was getting sucked flat when you put full lock on in either direction and making this knocking noise and this was tested while we were parked up.The noise got louder the longer you held the lock on then died off.The car is now going back in for further investigation to find the problem(s).Has anybody else had this sort of problem and if so what was it and what can i expect.Freelander TD4 2004.Regards Alan

Which flexible pipe is sucking in. If it's the pipe from the bottle to pump pipe it's likely the pipe has collapsed internally.