I had no problem at all with odor when I was on Meraviglia.   Chengkp75 knows all about this stuff (and many other things) so I'll just quote him.....   "The most common cause of sewer smells in cabins is the bathroom floor drain (not the shower), that typically hides under the toilet, or is a trough drain at the door. These drains see little water into them, so the dry air from the AC tends to dry out the water in the trap, and odors back up. A glass of water down these drai