Yealink SIP-T48G Administrator's Manual page 497

Configuring Audio Features
Parameters Permitted Values Default
When Y=4, the default value is 4;
When Y=5, the default value is 18;
When Y=6, the default value is 9;
When Y=7, the default value is 106;
When Y=8, the default value is 103;
When Y=9, the default value is 104;
When Y=10, the default value is 102;
When Y=11, the default value is 105;
For SIP-T27P/T23P/T23G/T21(P) E2:
When Y=1, the default value is 0;
When Y=2, the default value is 8;
When Y=3, the default value is 18;
When Y=4, the default value is 9;
When Y=5, the default value is 106;
When Y=6, the default value is 103;
When Y=7, the default value is 104;
When Y=8, the default value is 102;
When Y=9, the default value is 105;
Example:
account.1.codec.1.rtpmap = 0
Web User Interface:
None
Phone User Interface:
None
0 (Disabled), 10, 20,
account.X.ptime 20
30, 40, 50 or 60
Description:
Configures the ptime (in milliseconds) for the codec for account X.
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).
Example:
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