Yealink VC400 Administrator's Manual page 196

Administrator's Guide for Yealink Video Conferencing Systems
Parameter
To configure the audio input device via web user interface:
Click on Setting->Video & Audio.
1.
180
Description
Line In port on the codec and
video conferencing phone.
Line In + Wired Micpod -

selects microphone connected
to the Line In port on the
codec and VCM30 video
conferencing microphone
array.
Default: Auto.
If Line Input is selected as the

audio input device, the
near-end audio output device
will not play sound from the
Line Input device.
If "Line In + device" is selected

as the audio input device, the
near-end audio output device
will play sound from the Line
Input device.
During a video training for
main office and branch office,
both offices need to hear the
video sound, you can select
this option.
Configuration Method