Sounds of Solitaire is a novel interface for musical expression based on an extended peg solitaire board as a generator of live musical composition. The classic puzzle game, for one person, is extended by mapping the moves of the game through a self contained system using Arduino and Raspberry Pi, triggering both analogue and digital sound. The solitaire board, as instrument, is presented as a wood and Perspex box with the hardware inside. Ball bearings function as both solitaire pegs and switches, while a purpose built solenoid controlled monochord and ball bearing run provide the analogue sound source, which is digitally manipulated in real-time, according to the sequences of game moves. The creative intention of Sounds of Solitaire is that the playful approach to participation in a musical experience, provided by the material for music making in real-time, demonstrates an integrated approach to concepts of composing, performing and listening.