My car also got the sound, send to nissan check & they said is the steering coupling broken. Oledi replace but after 2 months, the sound still come back.
it doesn't broken...just got clearance aka free-play at the steering coupling...when got clearance,there's the "knock" when u turn the steering...
normally,what will the SC do is...for 1st and 2nd complaint...they will just re-tighten the coupling and the moving parts of the steering half-shaft by using G-clamp... they will only replace the new steering half-shaft for you at 3rd complaint...
this problem applied to most of the nissan latio and nissan livina...i think its due to the manufacture defect...if im not wrong...the new batch of the steering half-shaft with thicker grease also can't solve this problem...