When Martin tells Frasier and Niles that they cannot work together, he mentions the restaurant they bought and the book they tried to write together, referencing the events of The Innkeepers (1995) and Author, Author (1994), respectively.
In one scene, Niles refers to Frasier's program as a "sideshow." This could be an inside joke from the writers, as Kelsey Grammer had made frequent appearances as Sideshow Bob on The Simpsons (1989) since 1990.
The celebrity caller in this episode is Blair Brown, Blair plays a caller named Jill who has a recurring dream that Frasier (Kelsey Grammer) finds fascinating.
In this episode Frasier claims that his listenership is 500,000, with parts of Canada included. His radio signal would have to cover a lot more area than that because the average listenership for a top-rated program in the Seattle metro area in 1995 would only be 250,000 per week.