If that's for me - my car is 2003 06. So I don't have webasto fitted. Sound is like seat belt is trying to retract itself. And as I've said it is like buzzing sound. Maybe something in seatbelt tensioner? But I don't know if it is easy to remove that plastic cove and take a look.
I've searched myself looking for a thread, with a guide showing how to tackle common rattles. My car has a few.
A very annoying rattle from the top of the fascia (dashboard) has been bothering me. By chance, I noticed it stopped when the sun visor was down. So it was just a vibration from that (hard plastic to hard plastic).
Moral of the story is that noises echo. They do not always come from where you expect them to be. That's all.
I have your number 1 also ... but apart from that buzzing that is related to low revs my interior is silentSomeone needs to set up a "Call-out emergency rattle fixing" service!
I've currently got:
1. a buzz that comes from the steering column area which sounds a bit like an angry wasps' nest, but only when you're at pulling away from traffic lights/urban crawling stop/start kind of revs. V annoying. I hear this a lot.
2. a rattle that comes from the driver's side door card at about 40mph.
3. a buzz that comes from the passenger's side B pillar trim when using the phone via the RNS-E.
4. a vibration from I think the front left of the dashboard when pushing the engine a bit at around 1700RPM.
All of which seems to make the car feel more geriatric than it really is!