This parameter combines the actions of several other parameters into one, designed to quick-start applications needing high-quality audio. This parameter can be considered pretty heavy duty, so it's primarily designed for professional users needing near-raw audio quality, such as music DJs.
If used on the sender's side, it disable echo-cancellation, noise-reduction, and auto-volume leveling. It also requests stereo audio from the microphone source.
When applied to the viewer's side as well, it will increase the connection's audio bitrate to 256-kbps and request stereo-audio from the sender, if it is available.