Rattling noise behind the dashboard of my 2016 RX350

[skipthom]

At certain speeds I hear a rattling noise behind the dashboard of my 2016 RX350. It sounds like a piece of plastic rattling around. Has anyone else encountered this? How would one stop it?

[dancin]

Does it sound more like it is coming from the passenger side? If so it may not be behind the dash. Look underneath your car on the passenger side about where the gap between the front and rear door is about a foot or two in where the exhaust pipe runs. There is a flimsy heat shield attached to plastic with rivets. The rivets can get ripped out of the plastic and that heat shield will rattle around. That can sound like it is coming from the glove box area behind the dash

[Dmce]

I have a 2016 rx350 it has a rattle over bumps and pit holes had the struts checked out they seem good anyone change there seat bar bushings or something else?? 
thanks