I am constantly getting this error on a new build of FreePBX 13. I have removed trunks and it still continues. Any idea to fix this would be greatly appreciated. I do have many commercial modules installed but at this point don’t even know where to start.

Error[6641] chan_sip.c:4273 Serious Network Trouble; __sip_xmit returns error for pkt data

stevensedory (Steven Sedory) October 6, 2017, 6:10pm 6

Sorry to hear. We’re not using UCP, but seem to only have them on the servers in the environment explained here:

But here’s a post were some other users talk about it seeming to be related to UCP somehow: