The theme itself is ‘Frolic’ by Luciano Michelini, composed in 1974 for the film ‘La bellissima estate’ and used since then in some advertisements, in which Larry David had heard it. ‘Curb’ generally uses several old ‘production music’ pieces, i.e. those from a music library for films, tv and such. ‘It's Always Sunny in Philadelphia’ also does this.