Herelink v1.1 Air Unit packet loss


We recently bought the Herelink v1.1 and wanted to use the new ethernet connection on the top of the air unit. We have connected the the RX/TX (no ground connected) to one of our ethernet cables and the ethernet cable is going to another ethernet adapter. Pinging with this works 95% of the time but sometimes it says “Request timed out”.

If we go back to what we did with herelink 1.0, with usb micro ethernet adapter to another one the ping works 100% of the times.

Any idea what could be wrong? And if we need to connect the ground where would we do that?

Thanks in advance.

Can you share a photo of your set up(connect method and adapter) and the indication if you do not mind?