I compared the commands from kamailio->rtpengine between 5.1.1 and 5.1.2.
5.1.2 is ignoring DTLS=off:
5.1.1 "Good" SDP
b'record-call': b'on', b'DTLS': b'off', b'ICE':
b'remove', b'transport-protocol': b'RTP/SAVP', b'call-id':
b'9074afcb-0c7d-4b0d-b99f-e97634d077dd', b'received-from':
[b'IP4', b'10.13.20.14'], b'from-tag':
b'45a0d471-4ab2-48c6-b4fc-0b932ce90195', b'command': b'offer'}
5.1.2 "Bad" SDP
b'record-call': b'on', b'ICE': b'remove',
b'transport-protocol': b'UDP/TLS/RTP/SAVP', b'call-id':
b'be76321a-0072-4d91-a691-d1ab7a8ae46e', b'received-from':
[b'IP4', b'10.13.20.14'], b'from-tag':
b'cec50da3-e024-4915-bb7a-cd5822c23b09', b'command': b'offer'}
Anthony