Discovering outmoded or obsolete technologies and appropriating them in creative practice can uncover new relationships between those technologies. Using a media archaeological research approach, this paper presents the electromechanical relay and a book of random numbers as related forms of obsolete media. Situated within the context of electromechanical sound art, the work uses a non-deterministic approach to explore the non-linear and unpredictable agency and materiality of the objects in the work. Developed by the first author, Click::RAND is an object-based sound installation. The work has been developed as an audio-visual representation of a genealogy of connections between these two forms of media in the history of computing.