Symptom

After the call is established, if CUBE receives a re-INVITE from the called side with a=silenceSupp:off, automatically it considers the call is a fax call and switches over to fax, Local SRTP and remote srtp params are not being updated to the outleg for outgoing Invite towards SRTP leg

Conditions

Phone at the customer side calls phone at the Webex side. The call establishes OK and both parties talk. At some point during the call, Phone sends re-INVITE with a=silenceSupp:off. CUBE sends RTP Re-invite to Webex side [instead of SRTP] and gets 488 in response.

Workaround

Implement a sip-profile removing the a=silenceSupp:off voice class sip-profile 2 request ANY sdp-header Audio-Attribute modify "a=silenceSupp:off - - - -" "" voice service voip sip sip-profiles inbound sip-profile 2 inbound

Further Problem Description