From the mid 20th century into the 21st, artists and musicians manipulated, cracked and broke audio media technologies to produce novel, unique and indeterminate sounds and performances. Artists such as John Cage, Nam June Paik, Milian Kn��k, Christian Marclay, Yasunao Tone, Oval and Otomo Yoshihide pulled apart the technologies of music playback, both the playback devices � phonographs and CD players � and the recorded media � vinyl records and Compact Discs. Based in the sound expansion of the 20th century musical avant garde, this practice connects the interdisciplinary Fluxus movement with late 20th century sound art and experimental electronic music. Cracked and broken media techniques play a significant role in 20th century music and sound, and continue to be productive into the 21st. The primary contribution of this thesis is to provide a novel and detailed historical account of these practices. In addition it considers theoretical approaches to this work. After considering approaches through critiques of recording media, and concepts of noise, this thesis proposes novel theorisations focusing on materiality and the everyday. Ultimately it proposes that these practices can be read as precursors to contemporary new media, as music and sound art cracked open the fixed structures of �old media� technologies for their own creative purposes.