Yealink SIP-T48G Administrator's Manual page 695

Parameters
Note: It works only if the value of the parameter "voice.tone.country" is set to
Custom.
Web User Interface:
Settings->Tones->Dial
Phone User Interface:
None
voice.tone.ring
Description:
Customizes the ringback tone.
The value format is Freq/Duration. For more information on the value format, refer to
the parameter "voice.tone.dial".
Note: It works only if the value of the parameter "voice.tone.country" is set to
Custom.
Web User Interface:
Settings->Tones->Ring Back
Phone User Interface:
None
voice.tone.busy
Description:
Customizes the tone when the callee is busy.
The value format is Freq/Duration. For more information on the value format, refer to
the parameter "voice.tone.dial".
Note: It works only if the value of the parameter "voice.tone.country" is set to
Custom.
Web User Interface:
Settings->Tones->Busy
Phone User Interface:
None
voice.tone.congestion
Configuring Audio Features
Permitted Values
String
String
String
Default
Blank
Blank
Blank
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