Don't forget tidal pull.

No, not the moon (though that's a tiny factor, as well), but the only part of the ISS that's in true "zero-g" is its center of mass. The further in or out you go from the center of mass of the combined system, the further you are from a true free fall orbit, and that exerts a small tidal pull. It's even used to stabilize some satellites that want to have a particular aspect always facing down towards the gravity well.

Not saying that's what's happening in the video, but it's another possible cause for things to be settling in a microgravity environment.