Macbook Pro suddenly very slow on RBR750

[Bakermama]

Not techie, so please bear with me!

I installed the RBR750 mesh system with 2 satellites in early Sept.  Wired it to the ATT modem we already had, and the system has worked great until about Thanksgiving.  Did something update?  The lone MACBOOK pro in the household now cannot effectively use the internet.  All other systems are operating fine.

We have a guest network and tried to use that for the macbook pro, but still doesn't have effective speed (speedtest app in google showing as low as 10-15 Mbps for download speeds, varying with up to 48 Mbps for short periods).

Have latest firmware for ORBI.  Have unplugged and restarted satellites and main with no lasting impact on speed for that one device.

Have checked for Apple updates for the macbook and all is current.

Where do I start to get this resolved? 

[FURRYe38]

What Firmware version is currently loaded?

Has a power off for 1 minute then back ON with the ISP modem and Orbi system been performed since last update?

Is this the only device experiencing this? 

What is the Mfr and model# of the Internet Service Providers modem/ONT the NG router is connected too?

Built in router here? If so, This would be a double NAT (two router) condition which isn't recommended. https://kb.netgear.com/30186/What-is-Double-NAT
https://kb.netgear.com/30187/How-to-fix-issues-with-Double-NAT
Couple of options,
1. Configure the modem for transparent bridge or modem only mode. Then use the Orbi router in router mode. You'll need to contact the ISP for help and information in regards to the modem being bridged correctly.
2. If you can't bridge the modem, disable ALL wifi radios on the modem, configure the modems DMZ/ExposedHost or IP Pass-Through for the IP address the Orbi router gets from the modem. Then you can use the Orbi router in Router mode.
3. Or disable all wifi radios on the modem and connect the Orbi router to the modem, configure AP mode on the Orbi router. https://kb.netgear.com/31218/How-do-I-configure-my-Orbi-router-to-act-as-an-access-point and https://www.youtube.com/watch?v=H7LOcJ8GdDo&app=desktop

You can find other speed diagnosis steps in the community faq: https://community.netgear.com/t5/Orbi-AX/Community-FAQ-My-Orbi-speeds-are-slow-inconsistent-and-don-...

[Bakermama]

Thanks for the quick response.

Firmware Version is V3.2.16.6_1.4.4.  I don't know if this was what was installed in the 10 weeks or so that the macbook worked just fine, or if it was updated when I checked for updated firmware as one of my first thoughts about trouble shooting last week.

To be clear, the only device that is having a problem is the macbook pro.  And that device worked just fine for 10 weeks or so from install until about Thanksgiving.  The macbook is circa 2015 but we've updated software so it is current.

Have done the power off of main and satellites multiple times, with at least 1 min but usually more like 5 min break.  I plug in the satellites first and then the router--is that order correct?

The macbook has demonstrated the same speed issue when wirelessless on the main router or satellites.  I don't think I have any cables to do a wired connection. 

Modem is ARRIS BGW 210-700 from ATT.  I have not done the bridge or pass through modification.  Not a techie as I said, so when I unboxed the orbi and connected it, all worked just fine on all devices for weeks until last week.  And frankly, since all the other devices, including a work from home computer, are working ok, I am reluctant to make a lot of changes when IT WAS WORKING last week.  I'm worried I will mess up the rest of the accesses!

Other ideas?

Thanks

[FURRYe38]

Possible something wrong with the Mac Pro. Might contact Apple and check with them. If other devices are working fine and the Pro isn't, I would review whats going on with the Pro.