We have the strangest odor in our TT...it smells like an ash tray! (That's my best description.) We bought our TT in March, obviously used from CampingWorld and we were able to go into it and look ...
If it smells like "smoked salmon", it could be the coffee maker. Mine was a couple years old and something burnt-out in it. Kinda smelt like cigs or an ashtray.