When I leave and rejoin the IE dev server, all of my wires break, and I can recreate this consistently. Right now I only have LV wires, so I cannot test with other wire types. My wires all break regardless of whether they are between a connector and a relay or a connector and a connector. I cannot recreate this on a single player world. I haven't asked, but it seems like other players don't recreate the issue either. A picture of my setup is shown below.

I forced a crash with F3+C, here is the log: Crashlog

I'm running the server mod list with dev build #4, ImmersiveEngineering-1.17.1-5.0.2-pre.127.jar

Also having this problem; appears to happen on chunk load? Tried setting up wires inside a chunk (not across chunk lines) and same thing happened.

I added a capacitor to the line, and it stopped breaking.

However, other lines still break.