Something must have been hellishly wrong with Victory when you were there. We were in the Pacific (aft) dining room ourselves, ate there every night, and never heard or felt a peep out of the engines.
That could well be the case, I'm glad your experience was better. It only happened twice, once when we were backing out of port then started going forward, and once when we had turned around 1 hour out to return towards Miami with a medical emergency. We stopped beside another ship and unloaded the unfortunant family, then when we started moving again it got real noisy and vibrated a lot, just for a minute or two. Could easily have been something out of balance.