I originally booked an outside cabin 2473 in the very back, and it was unbearably shaking/ rattling / squeaking. The guest services moved us to a different cabin 6339 in the middle of the ship (a free upgrade to a balcony cabin), and that saved our vacation. I am very grateful to the ship management for moving us out of hell to heaven. However, even in 6339 the floor was noticeably vibrating, and the walls were occasionally squeaking. I thing there's something wrong with the ship's engine -- unbalanced or something of that nature.