Yealink SIP-T54S Administrator's Manual page 919

Details of Configuration Parameters:
account.X.dtmf.type
Description:
Configures the DTMF type for account X.
0-INBAND
1-RFC 2833
2-SIP INFO
3-RFC2833 + SIP INFO
If it is set to 0 (INBAND), DTMF digits are transmitted in the voice band.
If it is set to 1 (RFC 2833), DTMF digits are transmitted by RTP Events compliant to RFC
2833.
If it is set to 2 (SIP INFO), DTMF digits are transmitted by the SIP INFO messages.
If it is set to 3 (RFC2833 + SIP INFO), DTMF digits are transmitted by RTP Events compliant
to RFC 2833 and the SIP INFO messages.
X ranges from 1 to 16 (for SIP-T54S/T48G/T48S/T46G/T46S/T29G)
X ranges from 1 to 12 (for SIP-T52S/T42G/T42S)
X ranges from 1 to 6 (for SIP-T41P/T41S/T27P/T27G)
X ranges from 1 to 3 (for SIP-T40P/T40G/T23P/T23G)
X ranges from 1 to 2 (for SIP-T21(P) E2)
X is equal to 1 (for SIP-T19(P) E2/CP860/CP920)
Web User Interface:
Account->Advanced->DTMF Type
Phone User Interface:
None
account.X.dtmf.dtmf_payload
Description:
Configures the value of DTMF payload for account X.
Parameters
Configuring Audio Features
Configure the number of times for the IP
phone to send the end RTP Event packet.
Navigate to:
http://<phoneIPAddress>/servlet?p=feature
s-general&q=load
Permitted Values
0, 1, 2 or 3
Integer from 96
to 127
Default
1
101
893