Thanks for the advice, Aseem.
I have try this before. And CUCM still only offer one codec(G729) to TIPT. I just added the voice class codec back in. Below is the sdl log from CUCM.
Invite from CME
Content-Type: application/sdpContent-Disposition: ...
HI Aseem
The Call come from another SIP trunk Which is from CME to CUCM.
The completed Call flow is below:
SCCP phone --->CME--->SIP trunk----->CUCM --->SIP Trunk---> CUBE (Manage by SP)--> ITPT.
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