The Bad Son - S8-E3
Audio problem: Frasier is standing in his living room talking to Niles. We hear a knocking or tapping. As Frasier is expecting his date, Miranda, this might make sense, but they do not seem to hear it and make no move towards the door. A short time later the doorbell rings and Frasier's date arrives.
Answer: Nanny G (Nanette Guzman - played by Laurie Metcaf) has been a children's entertainer for twenty years, and tells Frasier, "Do you know what it's like to play the same character for 20 years?!" The joke is that Kelsey Grammer has been playing Frasier Crane since 1984, when the character first appeared on "Cheers", so Kelsey in real life has been doing just that!
Super Grover ★