When you hear the rattle grab ahold of the passenger front headrests and see if it goes! I too was convinced it was coming from that area, turned out to the be the sliders in the headrest! Also the top seatbelt loop, the one next to your ear sitting in the seat just flops about, I removed mine, wrapped a bit of electrical tape around the pivot section and noise gone!
Another thing to check is to open the front door, press in the rubber trim which runs down the black glossy plastic trim on the rear door and listen for it creaking! Mine were real bad as soon as the summer weather started, assuming the heat expanded the thin plastic!
And lastly, with the doors closed and you outside, press around the door frame, particularly close to where the doors meet and listen for creaking, I was astounded how bad mine were when the car was 6 month old, I mean really bad, once lubed up it sounded like a different car!
As you can tell over the last year I've pretty much eradicated every rattle and squeeks from the car, all trim removed, door cards etc all sound deadened!
. Driver seat is creaking in every corner, passenger b pillar has a rattle, door cards rattle with bassy music and now there’s a rattle somewhere in the central console 
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