I haven't experienced the problem you describe, but it sounds like there is a gasket not sealing properly or the door is out of alignment. ... or
Wasn't there a thread or post somewhere where someone was having a similar problem with the driver's door (I think) and it turned out the door was a little warped and the window frame area needed to be bent just a little?
Not as ominous as it sounds...

Maybe one of our Searchbots can find something...

 

Info posted in dvoffroad's other thread.

 

Sorry, I had seen this one first.

 

I have a 2001 Buick Century that generates the same noise with the back windows down. Never encountered that problem with previous cars. Good to know that when I get my HHR I will already know that this is normal.

 

First, let me thank those who began this site!!! Every vehicle should have one. Most excellent!!!
Now back to the issue at hand. Nearly scared me to death! Kids in the back decided they needed their windows down driving down the interstate. When the windows were just slightly open, I thought one, or both of my rear wheels was going to fall off! By the time the windows got all the way down, we thought our heads were going to explode. Those in this post who have said, "don't try this at home", are absolutely right. I'd be surprised if people haven't been hurt. NEVER have I had an experience like this, much less in a vehicle. I love my little red LS AA5, but I ain't never doing that again!!!