Where a clock frequency based on which encoding is performed has deviated over time, problems such as that an appropriate digital signal can not be outputted occur. To solve the problems, it is arranged such that when a decoder decodes video data and audio data, a control variable for controlling a frequency of a clock recovered by a clock generating portion is recorded as needed in a recording portion, and when the decoder decodes data recorded in the recording portion, the clock generating portion is controlled by using the control variable so that system time information generated by the counter synchronizes with time information extracted upon reception of a digital broadcasting program.