Yealink SIP T2 Series Provisioning Manual page 107

Parameter
features.key_as_send
features.send_key_tone
Permitted
Descriptions
Values
The default value is 0.
Note: It works only if the value of the parameter
"features.key_as_send" is set to 1 (Enabled).
It configures the "#" or "*" key as the send key.
0-Disabled
1-# key
2-* key
If it is set to 0 (Disabled), neither "#" nor "*" can be
0, 1 or 2
used as the send key.
If it is set to 1 (# key), the pound key is used as the
send key.
If it is set to 2 (* key), the asterisk key is used as the
send key.
The default value is 1.
It enables or disables the IP phone to play a key
tone when a user presses a send key.
0-Disabled
0 or 1
1-Enabled
If it is set to 1 (Enabled), the IP phone will play a
key tone when a user presses a send key.
Appendix
Web Setting Path
Features->General Information->Key
As Send
Features->Audio->Send Sound
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