Hello --

For several weeks, shortly after a flush, my toilet would make a loud chirping noise for about 30 seconds. It flushed perfectly and did not have constant running water or any leaks. The noise stopped by itself a few months ago.

-- What was it?

-- Why did it stop?

-- Is some part slowly going bad?

(I found a similar question in the archives the other day, but can't find the thread today for some reason.)