The radio control section 205 notifies a transmission rate that can be currently set up out of the radio channel transmission rates to the transmission rate decision section 207. The buffer monitoring section 208 monitors an amount of media data stored in the media reception buffer 209 and when the amount of media data stored exceeds a threshold, the buffer monitoring section 208 notifies it to the transmission rate decision section 207. When information on the radio channel transmission rate from the radio control section 205 shows that the radio channel transmission rate is well within the capacity and when monitoring information from the buffer monitoring section 208 shows that the amount of data stored in the media reception buffer 209 does not exceed a threshold, the transmission rate decision section 207 outputs a request for increasing the transmission rate of the media data to the control signal transmission/reception section 206. Thus, even if the maximum rate of the radio channel transmission rate that can be set up decreases due to deterioration of a communication environment, it is possible to prevent data play back from being interrupted.