Early in the episode, Malcolm McDowell hums a small portion of Ludwig van Beethoven's Symphony No. 9 in D Minor, Op. 125. The choral movement from this symphony figured prominently in Stanley Kubrick's film A Clockwork Orange (1971) which also starred McDowell.
During a break in rehearsal, one of the musicians asks for the symphony hall's wifi password. Betty Cragdale reveals that it it "PizzicatoFreak." Pizzicato is a technique used by string players where they pluck the strings of their instruments with their fingers, instead of playing with the bow, to create short percussive notes. Incidentally, Rodrigo plays pizzicato later in the episode, when at the end of his hospital performance he plucks the strings of his violin in time with Lazlo's heart monitor.
The piece that Rodrigo plays for Lazlo in the hospital is Vaughan Williams' The Lark Ascending. Written for solo violin and orchestra, it imitates the song and flight of the titular bird. It is a popular showpiece for violinists. The bit Rodrigo plays are the famous opening trills.