“B” pillar rattle - source?

[turns2stone]

I know we don’t have a ‘real’ B pillar
And I know it’s kinda crazy to think the internet can solve for a rattle, but I’ve given up hope trying to resolve, by myself.

On my 2019 i3S, there is a rattle from the driver’s B-pillar area, fairly high up, but not the roof area.
It’s not the rear door handle, and it’s not the seatbelt mechanism.

Is there any ‘known area’ to cause rattles near the top of the rear doors?

 

[turns2stone]

Well after several hours of troubleshooting every possible rattle point on both drivers side doors and contact points, I've decided that the rattle is coming from the driver's door window.

It appears to be loose somewhere inside the door panel and the rattling transmits up the glass to my ear height. Rolling down the window a bit makes the rattle go away.

The window height/position appears adjusted properly, and there's not any 'play' in the window itself when the door is open. It's just not tight enough inside its track or whatever.

I didn't see any good DIY videos for adjusting the window for this sort of symptom, please share if you've come across such a thing! Thanks.