HoloLens 2 cannot stablish wired connection using USB cable or ethernet-type C adapter.

Hello everybody,
In the company I work for, we have been developing a HoloLens 2 using Unity 2019.4.24 and MRTK 2.6.1 from about 5 years (we started in HoloLens 1) that basically connects to a PC software and sends and receives (using websockets) data to be rendered in the HoloLens.

A year ago, I made research to see if we can use a wired connection to perform the communications, and it used to work.

The setups I have tried (everyone used to work):

1. Connect the HoloLens to the PC using the USB cable and having the device portal enabled.
2. Using an ethernet to type C adapter, connect the HoloLens to a router using an ethernet cable, the PC is also connected to the router through ethernet.
3. Using an ethernet to type C adapter, connect the HoloLens to the ethernet port on the PC, in this scenario I needed to set an IP address and the submask in the PC and the HoloLens.

From my app side, everything worked without need to add special code to handle the wired connection. Last week one of our costumers told us that he is not able to use the wired connection (he was using the scenario 1), so, after I get the ticket, I tried to replicate the setup, for my surprise none of the setups were working. I restored the HoloLens device to the factory settings, doing this only scenario 2 works.

Besides this client, 2 of my colleagues are reporting the same issue, all our HoloLens have the OS version: 20348.1542, we have tried and old version of our app when I did the research, the app is not working so I’m assuming this could be a bug in the OS.

Other things I have noticed:

• The HoloLens is unreachable if I try to do a ping in scenario 1 a 2 (scenario 2 is reachable after restoring the HoloLens)
• In all scenarios the IPv4 is not shown/assigned, if I try to assign the IP manually in the IP assignment settings the configuration is not preserved, once I press “Save” and return to the previous screen, it remains “Automatic (DHCP)” and when is saved, the ping cannot reach the HoloLens from the PC.
• When I connect the cable 2 ethernet adapters are displayed (as far I remember there was only one).
• When the cable is not connected there’s still one ethernet adapter but cannot set an IP manually.

I was looking the way to try to perform a ping from the HoloLens, I was trying to use an app (DL Networks monitor) to see if the HoloLens is connected properly to the network.

As I mention above, this seems to be an issue to the Operating system, Where can I report this? The last idea to try to fix this is to downgrade the HoloLens to an older version of the OS and look if the wired connection works.