Unstable/inconsistent speed on Orbi RBK 852 AX6000 after upgrade to Spectrum Gigabit

[MikeElmendorf]

Hi, All -

New member of the community here.

I set up my new Orbi RBK 852 system (with two satellites) last Friday, replacing a series of Apple Airports I had been using for some time.  I had Spectrum cable internet with speeds up to 350.  

Previously, I would get that near the main router or on my Mac hardwired; throughout the house, though, it varied greatly.

The switch to Orbi brought immediately dramatic improvement; I was pulling down 350 pretty much everywhere in our house.

Yesterday,  figuring I'd take advantage of the much better capability of my new network setup, I had my Spectrum internet upgraded to their gigabit service, which required a new Technicolor modem.

Since then, I can best describe my speeds as unstable and inconsistent.

I'm able to sometimes pull down up to 700 or so on wifi when close to the router.  My Mac, which is hard wired, typically does better and hits in the 900s, but not always.  Other times, on wifi, I'm getting SLOWER speeds than when I was at 350 internet.  

Oddly, the internet speed also seems to accelerate more slowly, if that makes sense, when doing a speed test.  Previously, it would almost instantly peg at 350.  Now, it accelerates up and maybe it would get to a higher speed, but seems like it is still ramping up when the test ends.  Other times, it is just slow--slower than when I was at 350, which, again, was almost universal throughout the house before upgrading.  There's really no rhyme or reason to it.  I'm conducting these tests on an iPhone 11 Pro Max and a brand new iPad Pro, so both should be able to achieve peak speeds.

I've restarted the modem, router and satellites multiple times.  I also replaced the ethernet cable that had previously run from the modem to the prior router with the one that came with the Orbi, thinking maybe the old one was not capable of handling the higher speeds.  None of this has seemed to make much of a difference, if at all.

The higher speed is clearly there, but for some reason the wifi network doesn't seem to be handling as well as when I had a lower speed service, often producing slower wifi speeds now.

Any ideas on what else I might try?

Thanks in advance.

[FURRYe38 · Accepted solution]

Any Wifi Neighbors near by? If so, how many?

Be sure that CTS and RTS values are changed to 2346 under Advanced Tab/Advanced Settings/Wireless Settings

What happens if you disable AX mode to test...

[FURRYe38]

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

Has the ISP modem and RBR been powered OFF for 1 minute then back ON with the modem then the RBR? 

You should see near 900Mpbs speeds on a wired connection. Wireless, depending if you have AX support on your wireless devices and the design and speed support on those devices, I presume should need over 500Mpbs speeds. Most current AC mode supporting devices max out at around 400-500Mpbs wirelessly. Again depends on device design and support. Something to contact the Mfr about to see what they say. 

[MikeElmendorf]

Thanks for the reply, Furry -

The Orbi firmware is V3.2.10.11_1.2.12.

The modem model is E31T2V1.  I believe it is a Technicolor, based on what Spectrum has said, but it doesn't say much on the modem itself.

I have powered the modem and router off a number of times.  I'm not sure every time was more than 1 minute, but at least some of those attempts were.

[MikeElmendorf]

This is the modem:  https://d15yx0mnc9teae.cloudfront.net/sites/default/files/Spectrum_D31_eMTA_Data_Sheet.pdf 

[FURRYe38]

Ok, just checking for router with the modem. No router here. 

I would say Orbi is working well. Wireless speeds again will be based on enviroment, noise and device design and support. 

IF your getting near 900Mpbs on the wire, it's working...I know mine does. Though to get near 900Mpbs on wireless, I usually have to connect up my ASUS GT-AX11000 wireless bridge and I do see good speeds there. Thats the only AX client I have currently. I believe my D-Link DWA-192 adapter seen near 900Mpbs as well. 

[MikeElmendorf]

I guess what I'm struggling to understand is why, with a much faster connection, I would be seeing speeds lower than my old 350 at any time when I really did not before.  Also, the instability seems odd.

[FURRYe38 · Accepted solution]

Any Wifi Neighbors near by? If so, how many?

Be sure that CTS and RTS values are changed to 2346 under Advanced Tab/Advanced Settings/Wireless Settings

What happens if you disable AX mode to test...

[MikeElmendorf]

Furry -

I just changed the RTS and CTS values.  Will see how that works out; they were set to 64 or something like that, whatever the default would have been because I haven't touched it.

We live on a corner in a typical suburban neighborhood, so there are definitely wifi neighbors but we generally have not had issues with interference.

Wouldn't turning off AX mode negate the benefit of having purchased this router versus the less expensive Orbi?  Or are you suggesting that just as an experiment?

Thanks.

[FURRYe38]

Yes, NG seems to have started using 64 as a new default for those values. Seen odd problems since they started doing that. Seen some problems fixed by having users chane back to the old default values. 

Experiement only. I would disable it now. Then see how the system works with the new CTS values. If it seems to stablize and fix your problem, then re-enable AX mode. 

[Bandito]

Have you tried plugging your PC directly into the modem to do speed tests that way?  That will give you a better sense of the actual operation of the incoming signal before it gets to the Orbi.  If it shows similar variations or speed ramp-ups, then it could be an ISP issue.  If it's a solid connection at the modem, then there may be some issues with the Orbi.

[MikeElmendorf]

Furry - 

Changing the CTS and RTS values seems to have produced consistent improvement.  I did not tinker with the AX at this point; if I have more issues I will.

It also seems that I consistently get better/faster results if I use a server that is farther away for a speedtest.  I don't understand that.

[FURRYe38]

Some test servers are busier than others. 

Glad changing the CTS values helped. 

Please mark your thread as solved so others will know. 

Enjoy. 

[CallPaul]

That modem is a dog and a half. If you get spectrum 1gig Service they force that modem on you, they won't activate a user owned modem for that service. I had some of the same issues you're  having and couldn't figure it out so I swapped out their modem for a new one and it's working fine,

Check the dslreports.com website, there are boatloads of complaints about that modem. They distribute it under three different names, but it's the same modem.