Just be glad it's not a Filco error. Sounds like a Cherry Corp screwup.
You know perfectly that few pinging switches and the filco ringing problem are two different matter.
Got a Filco TKL today, and while is not ringing loudly like the ones mentioned by other users, it has a definite echo, that involves the whole keyboard.
Picking on the back of the keyboard is like picking on the back of a guitar, in this way some pinging switches will be amplified.
At least this explains why the push buttons are usually called "keys" in English :party: