Right Rear Door Noise

[Keithmaj]

Now that it has gotten a bit colder (40's), I've noticed an annoying intermittent buzz or rattle coming from the right rear door area. It also seems to be vibration induced when we traverse rougher roads and stops on smoother roads. Haven't been able to confirm it yet, but it might be related to the window shade as the noise doesn't seem to be as prevalent with the shade up. Has anyone else seen this? Wanted to check here before contacting CS...