At the beginning of the film when Caroline and Julian are at the restaurant, the space between them keeps changing between shots.
There's a scene in which, first Caroline's (Ruth Chatterton) suitor (George Brent) refers to his wristwatch, and then a moment later, her ex-husband played by John Miljan refers to his wristwatch...both watches are represented by identical footage in which the very same Elgin wristwatch is shown.
As Caroline and Julian are leaving the restaurant, a moving shadow of the boom microphone is visible on the frame and curtain of the doorway to the elevator, upper right.
When Caroline goes to Julian's apartment, about 22 min. into the film, a moving shadow of the boom microphone goes across the top of the open door as she enters.