A performance operator control apparatus adapted to a player piano comprises a motion control unit and a key drive unit comprising a plurality of key I/O control ICs in connection with keys of a keyboard, which are driven by solenoids so as to realize automatic performance, wherein upon detection of electrification abnormality of solenoids or temperature abnormality, LEDs are turned on to indicate the abnormality. The key I/O control ICs receive velocity signals regarding the solenoids so as to perform feedback controls on the keys in the automatic performance. In addition, unoccupied channels of the key I/O control ICs, which are not assigned to the keys and sensors, are used to input monitoring signals and to output inspection signals. Herein, the abnormality is determined based on the difference between pre-inspection data and post-inspection data, which are transferred using a loop connection channel of the key I/O control IC.