Yealink T46G Administrator's Manual page 177

Parameters
If it is set to 1 (Enabled), the LCD screen will present a new incoming call while during a call.
Web User Interface:
Features->General Information->Call Waiting
Phone User Interface:
Menu->Features->Call Waiting->Call Waiting
call_waiting.tone
Description:
Enables or disables the Skype for Business phone to play the call waiting tone when the
Skype for Business phone receives an incoming call during a call
0-Disabled
1-Enabled
If it is set to 1 (Enabled), the Skype for Business phone will perform an audible indicator
when receiving a new incoming call during a call.
Note: It works only if the value of the parameter "call_waiting.enable" is set to 1 (Enabled).
Web User Interface:
Features->Audio->Call Waiting Tone
Phone User Interface:
Menu->Features->Call Waiting->Play Tone
To configure call waiting via web user interface:
Click on Features->General Information.
1.
Select the desired value from the pull-down list of Call Waiting.
2.
Click Confirm to accept the change.
3.
Configuring Basic Features
Permitted Values
0 or 1
.
Default
1
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