yours can't be dirty surely!
by the way my passenger side had a terrible rattle which comes and goes (never happens with a passenger in though)
i traced it today to the felt trim with the heater vent holes in it which your talking about.
it rattles around a lot and i found if you bend the edge nearest the bulkhead up as much as you can it stops rattling
no i have a nice new rattle which sounds like a plastic clip or something sliding around inside the steering column shrouding. what a car