When Ray knocks over Marie's end table, they both pick up all of the items from the floor returning them to the end table. Later in the scene, the sofa arm rest cover appears on the floor and the items on the end table (lamp, phone, etc.), as well as the trays on the sofa, all change position without being touched again.
When Robert is playing the drums at the end of the episode, you can see the silhouette of a crew member walking behind the window in the upper left of the screen.