MY loo smells of wee too: just mysteriously, even after I clean it. not all the time, but it's going thru a smelly phase at the moment, and really bothering me, tho dh says he doesn't notice it.
I'm starting to think it's something to do with the weather, or it's coming up from outside..anything so I don't have to face that I might have to clean it every day....
So glad that someone else is experiencing this too.