After some troubleshooting - this only seems to happen when I specify a built-in grammar to trigger a DialogFlow event. Thoughts?
RECOGNITION-COMPLETE 107 COMPLETE MRCP/1.0
Completion-Cause: 000 success
Content-Type: application/x-nlsml
Content-Length: 783
<?xml version="1.0"?><result><interpretation grammar="session:fie...@field.grammar" confidence="99"><instance><query_text>how can I help</query_text><action>smalltalk.agent.can_you_help</action><parameters></parameters><all_required_params_present>true</all_required_params_present><fulfillment_text>I'll certainly try my best. How can I help?</fulfillment_text><fulfillment_messages><text><text>I'll certainly try my best. How can I help?</text></text></fulfillment_messages><intent></intent><intent_detection_confidence>0.999641</intent_detection_confidence><language_code>en-us</language_code><output_audio_uri>
http://localhost/utterances/umsgdf-102a08ecbdfd492d-1107.wav</output_audio_uri></instance><input mode="speech">how can
I help</input></interpretation></result>
CSeq: 1
Transport: RTP/AVP;unicast;client_port=35085-47360;mode=record
Content-Type: application/sdp
Content-Length: 208
v=0
o=- 123 456 IN IP4 10.10.10.120
s=Unified Contact Center Express 12.5.1.10000-31
c=IN IP4 10.10.10.120
t=0 0
m=audio 35085 RTP/AVP 0 96
a=rtpmap:0 pcmu/8000
a=rtpmap:96 telephone-event/8000
a=fmtp:96 0-15
2020-07-02 10:02:46:129194 [NOTICE] Create RTSP Session <5369649bdd334475>
2020-07-02 10:02:46:129232 [INFO] Create Session 0x7f276001a418 <new> [uni1]
2020-07-02 10:02:46:129253 [INFO] Add RTSP Session <5369649bdd334475>
2020-07-02 10:02:46:129313 [WARN] Cannot read the first field in start-line
2020-07-02 10:02:46:129334 [WARN] Failed to Parse RTSP Data
2020-07-02 10:02:46:129343 [NOTICE] Add Session <5369649bdd334475>
2020-07-02 10:02:46:129358 [WARN] Cannot read the first field in start-line
2020-07-02 10:02:46:129391 [INFO] Receive Offer 0x7f276001a418 <5369649bdd334475> [c:0 a:1 v:0]
2020-07-02 10:02:46:129409 [WARN] Failed to Parse RTSP Data
2020-07-02 10:02:46:129428 [INFO] Found MRCP Engine [GSS-1] for Resource [speechsynth] 0x7f276001a418 <5369649bdd334475>
2020-07-02 10:02:46:129431 [WARN] Cannot read the first field in start-line
2020-07-02 10:02:46:132950 [INFO] Media Path 0x7f276001a418 Source->[LPCM/8000/1]->Bridge->[LPCM/8000/1]->Encoder->[PCMU/8000/1]->Sink
2020-07-02 10:02:46:133133 [INFO] Open <5369649bdd334475@gss>
2020-07-02 10:02:46:133334 [NOTICE] GSS Usage: 1/1/2
2020-07-02 10:02:46:133436 [INFO] Send Answer 0x7f276001a418 <5369649bdd334475> [c:0 a:1 v:0] Status OK
RTSP/1.0 200 OK
CSeq: 1
Transport: RTP/AVP;unicast;client_port=35085-47360;server_port=5004-5005;mode=record
Session: 5369649bdd334475
Content-Type: application/sdp
Content-Length: 199
v=0
o=UniMRCPServer 0 0 IN IP4 192.168.86.159
s=-
c=IN IP4 192.168.86.159
t=0 0
m=audio 5004 RTP/AVP 0 101
a=rtpmap:0 PCMU/8000
a=rtpmap:101 telephone-event/8000
a=fmtp:101 0-15
a=sendrecv