Thunderbolt network adapter stopped working

Hello,

All of a sudden, my (original Apple) thunderbolt network adapter stopped working. I'm looking for tips to get it working again without reinstalling. This is the second time in 6 months it happened, and last time a reformat fixed it, and restoring my entire user account did not restore the problem, so all signs point to something in the core system and not userland.

Why I know the adapter is not the problem:

- Two colleagues' adapters also don't work

- Adapter works fine in recovery but not once booted

What happens when I plug it in:

- Network light turns on on the switch, so a link is established

- The adapter stays "red" in the network settings

- dmesg shows:

IOThunderboltSwitch<0>(0x0)::listenerCallback - Thunderbolt HPD packet for route = 0x0 port = 1 unplug = 0

[ PCI configuration begin ]

[ PCI configuration end, bridges 14, devices 15 ]

No obvious sign of problem.

Steps taken to troubleshoot:

- If I delete the adapter from the network settings, I can never add it again; it simply never shows up, even if it's connected and the link light is on on the switch.

- Wiped out /Library/Preferences/SystemConfiguration and rebooted. Still can't add the interface, as above, it never appears.

At this point I'm out of ideas. Any help would be greatly appreciated.

Thanks!