Anyone ever heard of A Face in the Crowd, a film from 1957? I found it through a Wikiwalk.

In late 1950s America, a drunken drifter, Larry Rhodes (Andy Griffith), is plucked out of a rural Arkansas jail by Marcia Jeffries (Patricia Neal) to sing on a radio show at station KGRK. His raw voice, folksy humor and personal charm bring about a strong local following, and he lands a television show in Memphis, Tennessee under the stage name “Lonesome” Rhodes, given to him on a whim by Jeffries.

[…]

The final blow is delivered by the one who has loved Rhodes the most and been most injured by his selfishness: Marcia Jeffries. At the end of one of Rhodes’ shows, the engineer cuts the microphone and leaves Jeffries alone in the control booth while the show’s credits roll. Millions of viewers watch (in what initially is silence) their hero Rhodes smiling and seeming to chat amiably with the rest of the cast. In truth, he is mocking Fuller, then going off on a vitriolic rant about the stupidity of his TV audience. In the broadcast booth, Jeffries reactivates his microphone, sending his words and laughter over the air live. A sequence of television viewers is shown to react to Rhodes’ description of them all as “idiots, morons, and guinea pigs”.

Still unaware that his words have gone out over the air waves (with thousands of angry calls to local stations and the network headquarters), he departs the penthouse studio in a jovial mood and prophetically tells the elevator operator that he is going “all the way down”. As the elevator numbers go down to 0, the show’s popularity is plummeting as well. DePalma is already meeting with a young entertainer who could become Rhodes’ replacement.

Rhodes arrives at his penthouse, where he was to meet with the nation’s business and political elite. Instead he finds an empty space, except for a group of black butlers and servants, by whom, in desperation, he demands to be loved. When they fail to respond, Rhodes dismisses all of them. Rhodes calls the studio and Jeffries listens to him rant as he threatens to jump to his death from the penthouse. Jeffries, who has been silent, suddenly screams at Rhodes, telling him to jump and to get out of her, and everybody’s, life.

Miller angrily dares her to face Rhodes and tell him the whole truth. They go to the penthouse and find Rhodes drunk and disconnected from reality. He shouts folksy platitudes and sings at the top of his lungs while his longtime flunky Beanie (Rod Brasfield) works an applause machine—Rhodes’ own invention—to replace the cheers, applause, and laughter of the audience that has abandoned him. When he vows to get revenge on the TV studio’s engineer, Jeffries admits it was she who betrayed him. She demands he never call her again, and Miller tells Rhodes that life as he knew it is over.

en.wikipedia.org