A data transmission method in which an equipment receiving data is prohibited from displaying a noisy picture or issuing an unusual sound which might possibly destruct a speaker. When the operating mode is switched from the stop state (Stop) to the playback state (PB) to start outputting data recorded on a recording medium, a data recording and/or reproducing medium equipment 20 sets a broadcast connection counter or a point-to-point connection counter from 0 to 1 on transition of the DIF mode (digital input/output mode) from IN to OUT to set a connected state. The data recording and/or reproducing medium equipment 20 inserts a DIT of tf=1 before releasing the muting.