I'd rather be on the ship so any deck would be fine with me.
But really.
I would avoid:
deck 1, since the rooms are only in one corner (port between midship and forward) you'll have to go to a different deck to get to the aft part of the ship. And in Nassau since you are on the same deck and area as the gangway (deck 1 forward) you'll get all the humidy in your hallway.
deck 2, right under the nightclubs, Kitchens, and if you are in 2626 area, right over the loading area.
deck 8, since it's right under the pools, and Topsiders/Beach blanket. You'll hear running, deck chairs scrapping, and power washing, and in certain area's that are under the goofy pool, the deck parties. Since all the premium categories (1,2,3 and 4 ) are all on this deck I wonder what the designers were thinking.
our favorite is deck 5, smack in the middle of everything
and you would not know the kids clubs were on the same deck.
decks 6 and 7 are all staterooms, so the only noise you hear are your neighbors. Sort of like at a hotel. hallway traffic, doors slamming.