Administrator's Guide for SIP-T23 & T23P & T23G IP Phones
2.
Select the desired value from the pull-down list of RFC 2543 Hold.
3.
Click Confirm to accept the change.
To configure call hold tone and call hold tone delay via web user interface:
1.
Click on Features->General Information.
2.
Select the desired value from the pull-down list of Play Hold Tone.
3.
Enter the desired time in the Play Hold Tone Delay field.
4.
Click Confirm to accept the change.
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