IEC 61937-3:2007 describes the method used to convey non-linear PCM bitstreams encoded according to the AC-3 and enhanced AC-3 formats. This second edition cancels and replaces the first edition published in 2003. It contains the following significant technical changes. The definition of the audio data-burst required to deliver enhanced AC-3 bitstreams has been added. The definition of the latency of an enhanced AC-3 decoder has been added. The use of pause data-bursts when delivering enhanced AC-3 bitstreams has been added.