Asus RT-AC86U Speed Issue

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Jamzy

Occasional Visitor
Hi all,


I recently bought the Asus RT AC86U and have updated to the Merlin firmware.

My ISP speeds are 200mbps, and I have speedtest'd on my ISP's router (now a modem - the Superhub 3 from Virgin Media) and achieved 200mbps.

This test was done in Router and Modem mode.

Changing the ISP to modem and connecting to the AC86U it works fine but the speeds have been reduced to 45mbps.

The speed is still 45mbps on the Asus firmware, Merlin firmware and with QOS on/off.
I have speedtest'd on all devices, wireless and wired and can only get a max of 45-46 mbps.
But the upload speed is 20mbps, which is the usual I get from the ISP.

Can you please help?
 

ColinTaylor

Part of the Furniture
Your setup ought to work without any speed reductions.

As a test I suggest that you put the Hub 3.0 back into router mode but leave the Asus connected to it.

It won't matter for testing purposes that you will now have one router behind another. If a client connected to the Asus can achieve full speed you know there isn't a problem with the Asus.
 

Jamzy

Occasional Visitor
Your setup ought to work without any speed reductions.

As a test I suggest that you put the Hub 3.0 back into router mode but leave the Asus connected to it.

It won't matter for testing purposes that you will now have one router behind another. If a client connected to the Asus can achieve full speed you know there isn't a problem with the Asus.
Thanks for the reply - are you suggesting that I use the HUB 3.0 as the main router?
Or are you suggesting ISB -> Hub 3.0 (Router) -> Asus -> Computer?
 

ColinTaylor

Part of the Furniture
Did you do a factory default reset (with initialise) after you installed the Merlin firmware?
 

ColinTaylor

Part of the Furniture
Maybe one of your Ethernet cables is bad? Can you try another one?

Have you made any changes to the router's config beyond setting up the user name, passwords and SSIDs?
 

Jamzy

Occasional Visitor
Maybe one of your Ethernet cables is bad? Can you try another one?

Have you made any changes to the router's config beyond setting up the user name, passwords and SSIDs?
I've swapped the ethernet cables around and used them with the superhub on it's own to test speeds, all showing 200 mbps with just the superhub.

I have not made any other changes, just the standard initial setup.
 

Jamzy

Occasional Visitor
Maybe one of your Ethernet cables is bad? Can you try another one?

Have you made any changes to the router's config beyond setting up the user name, passwords and SSIDs?
Just to note - I do get the max 200 mbps download speed if I speedtest as soon as I turn on the hub modem and it connects to internet.
But it then drops down afterwards to 45mbps
 

ColinTaylor

Part of the Furniture
Just to note - I do get the max 200 mbps download speed if I speedtest as soon as I turn on the hub modem and it connects to internet.
But it then drops down afterwards to 45mbps
Sorry, I can think of no logical reason why that would be happening. Maybe it's simply a hardware fault.

If you want you could upload the router's System Log to somewhere like pastebin so we can check it?
 

ColinTaylor

Part of the Furniture
Well I can't see anything obvious in the log. :( Maybe someone else can spot something and chime in.

Is the anything in the Hub's own log file? In modem mode go to http://192.168.100.1/ and click on Check router status > Network Log
 

ColinTaylor

Part of the Furniture
Here's the past of the hub log file!
https://pastebin.com/GQvt7Kie
Oh dear, that's not good.

RCS Partial Service

That means the modem can't synchronise properly with the headend. If the messages cover just a few minutes that's OK. But if it's all the time then there's a problem.

Have a look at the "Downstream" stats. If the modem is synced you should have about 12 or so active channels. When the modem can't sync it'll probably go into a boot loop, or settle on just one or two channels (giving a much lower speed).
 

Jamzy

Occasional Visitor
Oh dear, that's not good.

RCS Partial Service

That means the modem can't synchronise properly with the headend. If the messages cover just a few minutes that's OK. But if it's all the time then there's a problem.

Have a look at the "Downstream" stats. If the modem is synced you should have about 12 or so active channels. When the modem can't sync it'll probably go into a boot loop, or settle on just one or two channels (giving a much lower speed).
Ohh I see - is there any way you can recommend to solve this?
 

Jamzy

Occasional Visitor
Oh dear, that's not good.

RCS Partial Service

That means the modem can't synchronise properly with the headend. If the messages cover just a few minutes that's OK. But if it's all the time then there's a problem.

Have a look at the "Downstream" stats. If the modem is synced you should have about 12 or so active channels. When the modem can't sync it'll probably go into a boot loop, or settle on just one or two channels (giving a much lower speed).
Sorry forgot to link -

This is the downstream stats
 

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