I have a toilet that drips, drips, drips. It doesn't RUN, it DRIPS. I've had the stopper replaced (not sure if that's what you call it) but it still drips. There's no water coming out and really no signs of a water overflow anywhere but the dripping still continues. It's very annoying to the point where I just close the bathroom door at night so I can sleep. The plumber I had out was totally puzzled. He said I might have to replace the toilet. Is that the only fix?