As the CV rotates, if its badly worn it can lock and try and resist the rotation. Then it will suddenly release and continue turning...........its a bit more dramatic than a rattle, believe you me..........nearly through me off the road first time it happened on my Audi, scared the sh!t out of me. It actually knocked the steering over to the left in jolts as it rotated

They can just get noisy and rattle on a certain steering lock.
I would check out your top mounts and make sure its all secure up there first. Another thing you could try is jack the front end up and put the steering lock on. Then try rocking the wheel left and right, see if there is too much play in the strut and particularly at the top of the strut.