My heater is roaring all the time, I don't notice any sound getting any louder when drawing hot water.
I did forget to mention that the exhaust passes through the wall in my bedroom on the second floor (over the water heater). Is it normal for that wall to be very hot? I noticed the wall was very hot about two weeks before the hot water went out. It is hot all the time, there is no cool down period noted.
No need to get too involved, there's no way I could do this myself. I'm sure I need to call a plumber, I just don't want to get ripped off because I am ignorant.