Early last week an update for HD DVD set-top players which adds TrueHD 5.1 audio support was leaked. The 1.9b firmware which is said to work with Toshiba's HD DVD set top players has been tested by owners but is not supported by Toshiba just yet.
The 2.0 final release firmware should also add the capability to decode Dolby TrueHD audio which is a lossless format with up to an 18Mbps bitrate. TrueHD is a Dolby Labs technology which both supports up to 8 channels of audio and is a required capability for HD DVD set top players according to Dolby Labs specifications of the audio format.
A high-definition optical disc player can be connected to a supporting A/V receiver in one of two ways: through separate audio channels using analog inputs/outputs or through the HDMI and HDMI 1.3 interfaces. HDMI 1.3 readily supports Dolby TrueHD transport between A/V equipment. However, TrueHD is more of a technology between the content on the optical media and the player itself so home audio equipment that supports 7.1-channel audio inputs will be able to make use of this technology.
