Yealink SIP-T2 SERIES Administrator's Manual page 321

Details of Configuration Parameters:
Parameters
features.ringer_device.is_use_headset
Description:
Configures the ringer device for the IP phone.
0-Use Speaker
1-Use Headset
2-Use Headset & Speaker
If the ringer device is set to Headset or Headset&Speaker, the headset should be connected
to the IP phone and the headset mode also should be activated in advance.
Note: It is not applicable to CP860 IP phones.
Web User Interface:
Features->Audio->Ringer Device for Headset
Phone User Interface:
None
To configure ringer device for headset via web user interface:
Click on Features->Audio.
1.
Select the desired value from the pull-down list of Ringer Device for Headset.
2.
Configuring Basic Features
9G/T27P/T23P/T23G/T21(P)
E2/T19(P) E2:
http://<phoneIPAddress>/servlet?p
=features-audio&q=load
For SIP VP-T49G:
http://<phoneIPAddress>/servlet?m
=mod_data&p=features-audio&q=l
oad
Permitted Values
0, 1 or 2
Default
0
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