While an automatic player piano is reenacting a music tune, the automatic player piano sometimes fails to miss a tone or tones in a repetition due to a high-speed key movement; a controller searches a music data file for a series of key events expressing the repetition, and makes the key movements uniform without changing the lapse of time from the last key event before the repetition and the lapse of time to the first key event after the repetition so that the automatic player piano is less liable to miss a tone.