i had this problem and eventually it was diagnosed that it was the sleeve that runs through the inner wing where the top mount fastens had become loose inside the inner wing,
"temporary" solution by the garage was to splay the sleeve out so it doesnt move within the wing, that was done last august and so far has not made a sound since,
proper fix includes body shop opening up the inner wing to reweld the sleeve and then closing up the wing again, big bucks for that total fix so i echo the others, if its under warranty get it back for them to solve......
i also had a suspension part replaced which according to Nissan is a "known fault" but as mine was out of the warranty period it was up to me to pay for, including a new brake caliper and the labour it was a total of £490 before i could drive the car without it squeeking, car has since passed its MOT without any problems so im happy that the problem is solved but if it does return im going to get rid of the car, i dont fancy the bill for the proper repair....
like the Note but cant get used to the small boot space after having bigger cars in the past, wifes Almera has a far bigger boot space.