Yealink SIP-T4X Administrator's Manual page 161

2. Select the desired value from the pull-down list of BLF LED mode.
3. Click Confirm to accept the change.
To configure a BLF key via phone user interface:
1. Press Menu->Call Features->DSS Keys.
2. Select the desired DSS key.
3. Press or , or the Switch soft key to select BLF from the Type field.
4. Press or , or the Switch soft key to select the desired line from the Account
ID field.
5. (Optional.) Enter the string that will appear on the LCD screen in the Label field.
6. Enter the phone number or extension you want to monitor in the Value field.
7. (Optional.) Enter the directed call pickup code in the Extension field.
8. Press the Save soft key to accept the change.
Music on Hold (MoH) is the business practice of playing recorded music to fill the
silence that would be heard by the party who has been placed on hold. To use this
feature, specify a SIP URI pointing to an MoH server account. When a call is placed on
hold, the IP phone will send an INVITE message to the specified MoH server account
according to the SIP URI. The MoH server account automatically responds to the INVITE
message and immediately plays audio from some source located anywhere (LAN,
Configuring Advanced Features
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