Mac Studio's ethernet port has slowed down

[macsquared]

My Mac Studio's ethernet port may be faulty. The max transfer speed has dropped down to less than 100Mbps. I have AT&T fiber with 1G service and up until yesterday I was getting internet speeds well above 900Mbps up/down.
I've plugged the same ethernet cable into my MacBook Pro and am getting the full 1G service. I have a USB-C ethernet adapter and plug it into the Mac Studio, and again full 1G.

Am I right in thinking the ethernet port has gone bad?

 

[BanditoB]

I'd recommend disconnecting the Ethernet cable from your Mac Studio, shutting it down, letting it sit off for 30 seconds or so, and then turning it back on. Once on, reconnect the Ethernet cable and then retest your speed.

 

[sgjohnston]

First thing to try is a new ethernet cable (at least cat-5E).

 

[macsquared]

I'd recommend disconnecting the Ethernet cable from your Mac Studio, shutting it down, letting it sit off for 30 seconds or so, and then turning it back on. Once on, reconnect the Ethernet cable and then retest your speed.

Just tried that. No change. Not only is it slower, but it also takes a lot longer to find the ethernet connection than it did in the past.

First thing to try is a new ethernet cable (at least cat-5E).

Tried different cables. No change. But I also used the exact same cable using an USB ethernet adapter and got faster connection. So it seems the cable is not the issue.

 

[BanditoB]

It's probably time to schedule a Genius appointment, then.

 

[Fishrrman]

I recall reading posts from others who DE-activated a feature called (I think) "energy-efficient ethernet" -- and then had better results...