According to RFC3551, payload type 2 above (in the m=audio and the a=rtpmap:2) is reserved.
Entries in Tables 4 and 5 with payload type "dyn" have no static payload type assigned and are only used with a dynamic payload type. Payload type 2 was assigned to G721 in RFC 1890 and to its equivalent successor G726-32 in draft versions of this specification, but its use is now deprecated and that static payload type is marked reserved due to conflicting use for the payload formats G726-32 and AAL2-G726-32
Thus the PAP2T should not use payload type 2 at all. I believe this is a fault in the firmware.
Article ID:1966 Network Address Translation (NAT) Settings for Lines on
PAP2T and SPA3102 Phone Adapters Objective The objective of this
document is to configure Network Address Translation (NAT) settings for
the lines of communication on the PAP2T and SP...
Article ID:2742 Speed Dial Settings on SPA100 Series Objective Speed
Dial Buttons are often used to make the process of calling regularly
used contacts quicker and with one button. This option is used in place
of dialing the entire phone number in. This h...
Article ID:2676 Firmware Upgrade on SPA112 and SPA122 Objective To
upgrade the firmware a specific file must be downloaded from the
Internet and uploaded to the device. Upgrading your devices can be very
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