2010 Drivers Door Glass Hits Bottom Hard?

I've been looking around but haven't found any relative posts. Likely because it could be described many ways I guess. Anyway...
The drivers window in my 2010 base Mustang when going down hits bottom rather hard. There's a clunk when it stops. Auto and manual up and down work fine, it just clunks when it hits bottom. The passenger side stops smoothly without any clunk. I've tried pulling the fuse when the window is in motion to remove it's memory. Then plugging the fuse back in and running the window down all the way, holding the button down for 2 seconds, running the window up, holding the button up for 2 seconds then running the window up and down 5 times. Those instructions were found online for 2005 to 2009 Mustangs but I thought I'd give it a shot. It cured nothing. I don't know if there's a rubber bumper that fell off?
I'm afraid this is just a symptom of something worse coming, like the window falling off the track or something.
If anyone has any words of wisdom I would appreciate hearing them. Thanks to everyone for taking the time to view.
Jeff,

Sorry to hear that V. I still have the issue, it comes and goes. I've had a number of Mustangs and loved owning all of them. But this 2010 has been nothing but constant problems. Nothing major, just little things that never seem to end. As soon as one thing gets fixed something else comes lose or stops working.
Good luck with your window!