Inbound Calls through SBC intermittently dropping

[RAustin70]

CUCM 14SU3, SBC 8300 v17.09.04a

We moved off TDM PRIs over to new SBCs for all calling.  Testing since November with no issues.  We ported our DNs to the carrier on 17 April from our old carrier and I set up inbound calling to come in across the SIP Trunks, and outbound is still routing out over my TDM RGs until I verify inbound is solid.

I have been getting sporadic reports of people getting calls, picking up and the call drops anywhere between 2 seconds to like 2 minutes.  I have attached an example call from this morning, customer states they answer, hear the person on the distant end, and the call just disconnects.

We use SRTP and Secure Profiles as a requirement from the customer and the SIP Provider requires it also.  I'm thinking maybe a Media resource issue, but I am flush with them.  Any ideas on how to attack this?  I am new to SBC, what logs can I dig into?

[AEledge]

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@RAustin70 wrote:

what logs can I dig into?

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I would start with the following debugs on the SBC and try to capture an example. Throw the SIP messages into translator X or upload to the collaboration log analyzer and you should get a pretty good idea of where the issue lies. 

debug voip ccapi inout
debug ccsip messages

 Best of luck!