Rattle sound related to the DISA valve?

[snorrid]

I was hoping it was alright if I posted this here, this is not a ti but you guys seem helpful so I hope you wouldn't mind.

I have a E46 318i that has this strange rattling noise.

Here is a video with sound, hope you can hear it in the end.
http://www.youtube.com/watch?v=19jx5ka3VzY

You can't hear it when the car is cold, but after a couple of minutes of driving it becomes very audible inside and outside the car at low rpms.

Do you think its the DISA valve or something else?

p.s when I mean cold, the car is pretty much frozen.