Don't bring your stereo system!! Please....
A few cruises back we were waiting at embarkation and this young guy got in line behind us with his stereo on his shoulder and all I could think was "gosh, those poor people that will have to share a deck with him and that boom box".... Just my luck, we were the "poor people" that shared the deck with him. Good news though, by day 3 the boom box was at the purser's desk and we had mostly peace and quiet.