So I've just replaced my standard leaking shocks for a standard replacement, job went well with no problems. I've done 217 miles this morning since fitting and the the knocking noise started from the OSF, enough to hear it in the cabin on the move. Doing some diagnosis on they way home - around 60 and lift off the throttle to glide and the noise appears (rotational knocking). If I apply the throttle (any amount) the noise disappears. Again coasting and letting the speed reduce I applied the handbrake and the noise stays, so the front brake does have an influence. I'll try tomorrow in the car park where I can do a full lock turn.
Any ideas?