the silence of a voice that has gone — "Some listeners have actually come in…"
Some listeners have actually come in and down through the deep cortex and into the cold pink studio itself, to inquire. Some to allay this firm conviction that Madame was still actually still showing up and sitting there by the mike but not saying anything.
Context
The engineer monitoring a dead microphone distinguishes the theme's two silences: the silence of a present person choosing not to speak, and the silence of pure absence — and the second is unbearable. The damaged late-night listeners who trek into the studio to check whether the voice is still there, mutely present but withholding, are the far end of broadcast intimacy: people who cannot tell a withheld presence from a total absence, inquiring after a person who was only ever a voice and is now not even that.