There is provided a music accompaniment apparatus that is connected to at least one external device to reproduce an audio or video signal, the music accompaniment apparatus including: an audio input section for inputting an external audio signal; an audio signal processing section for processing an audio signal including an accompaniment signal internally provided and an external audio signal input through the audio input section, and externally outputting the processed audio signal; a video signal processing section for processing a video signal including a caption signal, and externally outputting the processed video signal; a time delay calculating section for calculating the difference between a transmission time of a check signal to the at least one external device and a reception time of the check signal from the at least one external device to compute a time delay representing a delay of the audio or video signal for the at least one external device; and a control section for controlling the whole operation of the music accompaniment apparatus including generation and transmission/reception of the check signal, and controlling the transmission time of the video or audio signal in correspondence to the time delay. The present invention guarantees an efficient use of a digital device having a time delay as connected to the music accompaniment apparatus.