A reproduction process device comprising: an input unit configured to receive a reproduction instruction of content data; and a reproducing unit configured to output the content data in a DoP format to an external reproducing device (2,4) through a Digital-to-Analog Converter, DAC, connectable to a Universal Serial Bus, USB, port based on the reproduction instruction received by the input unit, wherein the DoP format is a Direct Stream Digital, DSD, Audio over PCM flames format, wherein the reproducing unit includes: an acquiring unit configured to acquire a sampling rate of the content data having the DoP format which is an object of the reproduction instruction received by the input unit, as a first sampling rate; a notifying unit configured to notify the first sampling rate acquired by the acquiring unit to the external reproducing device (2,4); and a data control unit configured to output reproduction start notification data to the external reproducing device (2,4) for causing the external reproducing device (2, 4) to start a muting operation after the notifying unit notifies the first sampling rate, then output soundless data of DoP format corresponding to a predetermined length of time to the external reproducing device (2,4), and thereafter, output the content data having the DoP format which is the object of the reproduction instruction received by the input unit, to the external reproducing device (2,4), and wherein the data control unit outputs offset data representing a data output position of the content data which is being outputted, together with the content data, and wherein the offset data represents the data output position of the data excluding the soundless data. an input unit configured to receive a reproduction instruction of content data; and a reproducing unit configured to output the content data in a DoP format to an external reproducing device (2,4) through a Digital-to-Analog Converter, DAC, connectable to a Universal Serial Bus, USB, port based on the reproduction instruction received by the input unit, wherein the DoP format is a Direct Stream Digital, DSD, Audio over PCM flames format, wherein the reproducing unit includes: an acquiring unit configured to acquire a sampling rate of the content data having the DoP format which is an object of the reproduction instruction received by the input unit, as a first sampling rate; a notifying unit configured to notify the first sampling rate acquired by the acquiring unit to the external reproducing device (2,4); and a data control unit configured to output reproduction start notification data to the external reproducing device (2,4) for causing the external reproducing device (2, 4) to start a muting operation after the notifying unit notifies the first sampling rate, then output soundless data of DoP format corresponding to a predetermined length of time to the external reproducing device (2,4), and thereafter, output the content data having the DoP format which is the object of the reproduction instruction received by the input unit, to the external reproducing device (2,4), and an acquiring unit configured to acquire a sampling rate of the content data having the DoP format which is an object of the reproduction instruction received by the input unit, as a first sampling rate; a notifying unit configured to notify the first sampling rate acquired by the acquiring unit to the external reproducing device (2,4); and a data control unit configured to output reproduction start notification data to the external reproducing device (2,4) for causing the external reproducing device (2, 4) to start a muting operation after the notifying unit notifies the first sampling rate, then output soundless data of DoP format corresponding to a predetermined length of time to the external reproducing device (2,4), and thereafter, output the content data having the DoP format which is the object of the reproduction instruction received by the input unit, to the external reproducing device (2,4), and wherein the data control unit outputs offset data representing a data output position of the content data which is being outputted, together with the content data, and wherein the offset data represents the data output position of the data excluding the soundless data.