Ethernet cable not working between router and laptop

[#1]

None of these devices appears to be your USB Hub, it looks like its not even plugged in or if it is could it be broken?

Have you checked it on the other Mac?

[#2]

No. Will do that now.  HOWEVER, the hub has a lightning power cable port, a Mouse USB cable and an iPhone charger - all working fine. Might it simply be the ethernet port, do you think?

[#3]

Have you tried your landline phone?

See if there is any noise on your line - do a 17070 option 2 quiet line test. The whole point in that is it should be silent and if there is any noise it will be affecting your broadband. I have had to do this.

As you've tried a different cable with no luck, it should rule that out being the problem.

Other thing I can think of is the router has given up the ghost. That has happened to me as well.

If you have a spare try that. 

[#4]

It could be but it's odd that it's not showing in the list of device. You need to test it on another device just to make sure it works.

[#5]

Thanks, Alex. Did the quiet line test and all silent.  I'm getting closer to narrowing it down to the router or the USB hub.  The quest continues!

[#6]

No problem @Scrinson 

Is it possible to remove the USB hub from your setup to rule that out? I don't know if that will be easy for you to do.

If I were a gambling person (which I am not), my money would be on an iffy router.

[#7]

I'm afraid not, @Alex  It's quite a recent MacBook Air and only has two Thunderbolt 3 ports which means USB or Ethernet requirements get a little tricky.

[#8]

Fair enough.

The only thing I can think of is getting another USB hub (if you don't have a spare). Yep, it is a gamble if it doesn't make a difference. The one you have could be on its way out. The only thing I can suggest is try other devices in it and see if you notice any problems.

[#9]

If your WiFi's temperamental @Scrinson try disabling IPv6