18AudioAudio Channel Full duplex: Select it for simultaneous communication in both direction between the connectedadministrator and IP CAM. It means both parties can speak and be heard at the same time. Half duplex: Select it for communication in both directions, but only one direction at a time. It cannotreceive signal until the transmission has been done. Therefore, once one party speaks but can’t hear thevoice, and vice versa. Talk only: It narrows down to one way just for talking. Listen only: It narrows down to one way just for listening.Audio InputSelect the microphone input gain value you wish in the drop-down menu, and based on your region to select theproper codec and save all settings. G.711 U-law : one codec for “Computer Audio”, used in North America & Japan areas. G.711 A-law : another codec for “Computer Audio”, used in Europe and the rest of theworld. AMR Audio: an audio codec of the third generation communication for mobile.PHONE. While the option selected, your mobile phone will receive the audio file fromIP Camera. And you can choose the bit rate from 4.75k to 12.2k. However, the usage ofthis codec will cause frame-rate decreasing. Off: audio file won’t be transmitted by IP CAM.Audio OutputSelect the speaker output gain value you wish in the drop-down menu and save it.