This movie is about an old time radio show. In it the M/C had a deep baratone voice and has to sing his own jingles and do his own commercials. He stands at a podium. Each segment seems to have a different band or singer/entertainer. And he fills in while they are getting ready for they're act. There are two caracters in the movie that seem to have been regulars on the show for a long time, a lady country singer and an old man. Near the end of the movie these two are in the dressing room fooling around, when he has a heart attack and dies. But the show must go on.
I'm sorry I don't know the name of the movie nor any of the actors. Not much help I know. The M/C kind of sounded like Dallas Wayne.
It was a very good movie an I just happened upon it part way through.

A Prairie Home Companion (2006) ?
Starring Garrison Keillor, Woody Harrelson, John C. Reilly, Meryl Streep, Tommy Lee Jones
IMDb synopsis:
"A Prairie Home Companion", hosted by humorist Garrison Keillor, is a down home radio variety show recorded and performed live in front of an audience in a theater in St. Paul, Minnesota. A show from another era, it has been canceled. The regulars are performing on the last show, including Dusty & Lefty, singing/guitar-playing cowboys with a risqué sense of humor; and The Johnson Girls, a sister singing duo of Rhonda and Yolanda, who have a penchant for talking over each other. As the show goes on, the regulars, talk about their lives in relation to the show. Other goings-on include Yolanda and others trying to convince her shy, somber daughter, Lola, to sing on this last show. As all this goes on, a mysterious woman in a white trench coat who is on a mission wanders around the theater, while the show's dim security guard, Guy Noir, who usually has nothing to do security-wise, follows.

A Prairie Home Companion (2006) - IMDb