Symptom
RTP NTE packets leaving the software MTP running on the ASR have
incorretly the payload type set to 0
Conditions
Calling --- CUCM -- SIP --- MTP (ASR) --- Called
Software MTP allocated runs on the ASR
calling does OOB DTMF
called does inband RFC2833 DTMF
When CUCM receives OOB DTMF from calling it instructs MTP to generated
inband/RFC2833 DTMF to called.
The payload for these is always 0 regardless of what is negotiated on the SIP
