Oddball issue involving the driver's side door

Haven't seen this posted anywhere else, but for some unusual reason, which I feel must be attributed to heat expansion, etc my driver's side door after it has been sitting in the sun for a bit will make creaking and cracking sounds after I get in and start driving. It's rather unusual, and I feel like that door must not be forming a tight enough seal, but I cannot deduce why it would do that unless it had room to flex... which in theory, once closed, it probably shouldn't. No accidents or impacts to the door or any tinkering with the door in any way except to replace a bad window regulator once.

Having the same problem. Did it end up being the window regulator?

Edit: Just re-read and saw you were talking about the door itself. In my case it's the window when rolling down. Must be the regulator right?

When I first bought my GTI 2 years ago my B-pillar creaked like a pirate ship in the summer time anytime I'd drive over a bump or go up an incline. It's completely gone now. Although now it sounds like there's a loose screw rattling around somewhere in the center console area anytime I come to a stop at a light. :-/