Yealink T46G Administrator's Manual page 193

Parameters
features.play_hold_tone.delay
Description:
Configures the interval (in seconds) at which the Skype for Business phone play a warning
tone when there is a call on hold.
If it is set to 30 (30s), the Skype for Business phone will play a warning tone every 30 seconds
when there is a call on hold.
Note: It works only if the value of the parameter "features.play_hold_tone.enable" is set to 1
(Enabled).
Web User Interface:
Features->General Information->Play Hold Tone Delay
Phone User Interface:
None
To configure call hold tone and call hold tone delay via web user interface:
Click on Features->General Information.
1.
Select the desired value from the pull-down list of Play Hold Tone.
2.
Enter the desired time in the Play Hold Tone Delay field.
3.
Click Confirm to accept the change.
4.
Configuring Basic Features
Permitted Values
Integer from 3 to 3600
Default
30
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