A system, method, and wireless communication device that allow the transmission of secondary data in a group-communication data stream between wireless communication devices across a wireless communication network. The wireless communication device selectively transmits at least group-directed voice communication data to other members of a communication group, such as a push-to-talk (PTT) group, in a communication channel having a limited bandwidth thereof, and can selectively transmit secondary data in the same communication channel. A group-communication server preferably receives the voice communication data and secondary data and selectively transmits at least the voice communication data to other member wireless communication devices of the communication group. In one embodiment, the wireless communication device reduces the data size of the voice communication data to a second data size that is less than the bandwidth of the communication channel such that secondary data can be transmitted within the communication channel.