The vibration was determined to be caused by interference between the wake of the outer propellers and inner and became worse when turning. At high speeds the vibration frequency resonated with the ship's stern making the matter worse. The solution was to add internal stiffening to the stern of the ship but this necessitated gutting the second-class areas and then rebuilding them. This required the addition of a number of pillars and arches to the decorative scheme. The ship was finally delivered to Cunard on 26 August although the problem of vibration was never entirely solved and further remedial work went on through her life.