This episode draws a lot of inspiration from Pitch Perfect. The title of the episode is an antonym of the film's title, Pitch Perfect vs Tone Deaf.
Beckett gives her fake lover the name "Dr. Livingstone", and later at the loft, greets Castle with the quip "Dr. Livingstone, I presume?". David Livingstone was a 19th century missionary and explorer who disappeared in Africa in 1865; when journalist Henry Morton Stanley found him in 1871, Beckett's quip was Stanley's now-famous greeting.
At the beginning, as Beckett gets dressed to return to work, she and Castle discuss LokSat, and she calls him "007", an obvious reference to James Bond. The first Bond novel, "Casino Royale", is what inspired him to pursue writing as a career, and in When the Bough Breaks (2009), he was approached with the opportunity to write a new novel in the series. Furthermore Stana Katic starred in 007 franchise Quantum of Solace (2008).
During a scene where a suspect runs away, the chase music is a cappella.
To keep up the façade that she and Castle have broken up, Beckett tells Ryan and Esposito that she's dating a new man who works as a doctor. Josh Davidson, the boyfriend she dated before Castle, was a doctor.