I have the same problem and it's NOT the awning, or the Table in the door (still does it when I remove the table). It's definitely the door, I put my grandson in the back to tell me where it was coming from.
When you say 'check the rubber pad in the housing' HC - check it for what? It's definitely there and it's not damaged.
I did follow the link but it took me to another thread, not a vid?
The rattle from the rear door window blind area turned out to be an easy fix, although I haven't got around sorting it yet. The problem on our Beach is caused by the blind handle rattling against the rear door card. Two of those small clear stick on squidgy cushiony dome shaped things short sort it out.- try padding the table legs? - could be rattling on the back (underside) of table. even better, take it out & have a test drive - often doesn't click home properly.
- I've also had gravel (surprising amount!) in the groove under the side step where the door slides on my previous T5.
- try unmounting the awning altogether to eliminate it, thread about that recently.
- check your windscreen wiper blanking plugs & the wiper box 'outside' behind the vents under the screen. the windscreen collects all kinds of noise/s & reflects them back in weird ways, rattle could be coming from somewhere very surprising ...
- sit in the van engine off & get someone to rock it from the outside?
- check & double check every cubby hole & bottle holder
- someone had a rattly rear side window blind, may have been @Borris ?, can't remember
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