NX_ASSERT in ip_header_add.c

I am seeing a Random NX_ASSERT occurring in nx_ip_header_add.c (SSP 1.7.8, File version 5.12 using netx Duo and netx mqtt) on line 140. It appears to be failing some packet pointer check. This assert spins in sleep forever and it has the IP stack protection mutex, so everything network related ultimately gets hung up.
You can see in the attached TraceX screenshot that the mqtt publisher thread starts sending up through "SS" (Socket Send) and is then interrupted by the Ethernet Receive IRQ, which process a receive packet and causes some form of return packet to be sent (I guess but don't know for sure that this is a MQTT keep alive?); following this MQTT Publisher starts running again, and you can see at time just after 270730, a DS (Data Send) call by the MQTT publish thread and then it goes TZ (thread sleep) due to the NX_ASSERT failure. As can be seen by this call stack in the debugger: slack-files.com/TVANCBVPX-F01KS9H0VSL-3411a429b4

Has anyone else ever seen this, or have any ideas how to address/further debug this?

Thank You, Josh Patterson