Without being there, it is hard to tell.
I will let you know though, that the source of rattles could be in a totally different location than where they seem to be coming from. Case in point: I had several CD jewel cases in the center console that would rub together and make squeaking sounds. The sounds appeared to come from the dash.
Another possible source of rattles are the fold down rear seats. If they aren't fully latched in the upright position, they can make some noises, and may even appear to come from the dash.
Other sources of rattles are items stored in the car.
For a test, take EVERYTHING out of all compartments, bins and trays in the car, and take the items out of the car. If the rattle disappears, it was one of your carry-on items.