Yealink T46G Administrator's Manual page 191

Details of the Configuration Parameter:
phone_setting.is_deal180
Description:
Enables or disables the Skype for Business phone to deal with the 180 SIP message received
after the 183 SIP message.
0-Disabled
1-Enabled
If it is set to 1 (Enabled), the Skype for Business phone will resume and play the local
ringback tone upon a subsequent 180 message received.
Web User Interface:
Features->General Information->180 Ring Workaround
Phone User Interface:
None
To configure 180 ring workaround via web user interface:
Click on Features->General Information.
1.
Select the desired value from the pull-down list of 180 Ring Workaround.
2.
Click Confirm to accept the change.
3.
Parameter
Configuring Basic Features
=features-general&q=load
Permitted Values
0 or 1
Default
0
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