I'm living in a recently built apartment in Germany. There are many ethernet wall socket in each room. When connected my Macbook to the router directly with a cat 5e cable I can get around 800 mbps but I want to use the ethernet wall socket instead but it gives me only 100 mbps. Note that I have a gigabit contract. I'm using same 5e cat cable. My only theory is that the ethernet cable installed in the walls connected to the socket walls is causing the issue. But when I have opened it it seems like they are using cable cat 7. I have attached a screen shots of the socket. Do you have an idea what can be the issue ? or how can I investigate further ?
Update 1: I have tested all ethernet sockets of the apartment and I found that 3 of them are having issues but I was able to get the 800 mbps with the other wall sockets. Do you know what can be the issues with the 3 sockets that have a limited speed to 100mbps ?
Update 2: Here is an example of a socket that is working fine:
and the other end: