It should also be noted that the difficulty sleeping being attributed to the the quietness of the A380 is probably more about the positioning of the crew rest and the lack of noise insulation than it is about the aircraft being 'too' quiet.
The 767 never had a great crew rest but QF stuck some insulation on one of them and it was a significant improvement on the older ones. Unfortunately they never extended it to the rest of the fleet and it's a moot point on the 767 now anyway.....or at least it is for junior scum like me!
