David co-hosted Through the Keyhole in April 1992. After his co-presenter posed the question of who lived in the Doctor's TARDIS, obviously so on account of the Cloister Bell, he handed back to David in the studio. (NOTVALID: The Year Ahead)
Behind the scenes
David and his co-host are clearly references to David Frost and Loyd Grossman, who were the two presenters of Through the Keyhole in 1992.