I have a 2016 Highlander XLE and the 2nd row seats rattle terribly. Does anyone know a fix?

What is your question?

Riding down a smooth road or a bumpy road the seats rattle to where you can see them move in the rear view mirror. I asked toyota care and they acknowledge the problem, that all of the bench seats do this and they won't fix them.

What makes this problem better or worse?

nothing changes the problem no matter what road I drive on.

How long has your 2016 Toyota Highlander had this problem?

since I bought the car in Dec 2016