Akai AK3220HD User Manual page 24

Option
Balance
AVL (Auto
Volume Level)
Surround Sound
S/PDIF Mode
AD (Audio
Description)
Switch
24 | TV SETTING MENUS
Description
Adjust the audio output between the left and right speakers.
Turn on to keep the volume level consistent.
Turn ON/OFF surround sound effect from your TV speakers.
Set the digital sound output setting.
Audio Description (AD) provides an additional audio track for visually challenged persons
(DTV only, subject to program).