A communication device configured to receive messages containing media over a communication network and to receive locally created messages containing media created using the communication device. The device also includes a time-shifting buffer to store in a time-based format the media contained in both the messages received over the communication network and the locally created messages. The time-shifting buffer enables on the communication device to either (i) render the media received over the network in a near real-time mode; or (ii) render both the media received over the network and the locally created media in a time-shifted mode by retrieving the stored media from the time-shifting buffer. The communication device also includes a message management system, which enables the communication device to transition the rendering of the media between the time-shifted mode and the near real-time mode without interrupting the ongoing storage of media of received messages into the time-shifting buffer.