Our New TT (May-2020) has a Electric/Propane water heater that has become very noisy lately. If only it were not right next to the bed. But it is and the 2' proximity with a very thin wall for seperat...
Speaking for myself, I turn it off at night so I don't have to listen to it run. Water will stay hot for quite a while, and still plenty warm in the morning. I just flip the switch when I get up in the morning to make my first coffee and let it cycle.
The anode is not related to the sound it makes running.