Yealink SIP-T48G Administrator's Manual page 283

Parameters
Account->Advanced->DTMF Payload Type (96~127)
Phone User Interface:
None
account.X.dtmf.info_type
Description:
Configures the DTMF info type when the DTMF type is configured as "SIP INFO",
"RFC2833 + SIP INFO" for account X.
0-Disabled
1-DTMF-Relay
2-DTMF
3-Telephone-Event
X ranges from 1 to 16 (for SIP-T48G/T46G/T29G).
X ranges from 1 to 12 (for SIP-T42G).
X ranges from 1 to 6 (for SIP-T41P/T27P).
X ranges from 1 to 3 (for SIP-T23P/G).
X ranges from 1 to 2 (for SIP-T21(P) E2).
Web User Interface:
Account->Advanced->DTMF Info Type
Phone User Interface:
None
features.dtmf.repetition
Description:
Configures the repetition times for the IP phone to send the end RTP EVENT packet
during an active call.
Web User Interface:
Features->General Information->DTMF Repetition
Phone User Interface:
None
features.dtmf.volume
Description:
Configures the frequency level of DTMF digits (in db).
Configuring Basic Features
Permitted Values Default
0, 1, 2 or 3
1, 2 or 3
Integer from
-33~0
0
3
-10
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