GS-AX5400 WiFi Gradual Slowdown (2.4ghz specifically)

[w_dolph]

Apologies if wrong forum category, my issue is specifically with the Wireless on my ASUS router however.

Pretty much as the title reads, my GS-AX5400 has a perculier problem where the 2.4GHz band creeps to an eventual crawl and requires a router reboot, which then immediately fixes the speed on that band*.

This cycle was noticable after a few months of owning it but I persevered as it only needed doing every 4~ weeks, but either with 'age' or the newer firmware, it's currently every 3~5 days that I'm needing to reboot the router to restore the 2.4GHz wifi speed.

I'll use some simplified numbers here to give an example scenario:

Fresh router reboot -> spdtest @ *150mbps down (wifi) -> 3~ days pass -> spdtest @ 2~20mbps down (wifi) if I'm lucky. It gets to the point it fails to connect to speed test tools. -> repeat.

The 150mbps is the very rough average that the 2.4GHz devices get at common usage point of the house, it's not an optimal lay out, but that's not the issue here. At it's worst, I can hold my phone within 1m of the router and the speed would remain nearly unusable.

So I guess I'm getting around to asking: Is this a known issue with this model, something I can fix or address or should I start looking for a new router?


- Broadband is 1000 down 100 up.
- The 5GHz band also suffers a *slight* slow down but not comparable to the 2.4GHz band.
- Router aprox. 20 months old, bought new.
- Wired connection(s) doesn't mimic this behaviour at all.
- Latest firmware + got the "fancy" UI, forgot what it's called, came shipped with it.
- Mostly stock / auto settings, 2.4 & 5GHz band ran seperate (Smart connect off)
- Nothing is sapping the connection from a device according to traffic analyzer, even had a scenario where there was nothing connected to it at all for a few days and it still occurred when subsequently connected too.


Thanks in advance for any help offered,

Dolph.

 

[L&LD]

Welcome to the forums @w_dolph.

The best/fastest way to troubleshoot this is to do a full reset to factory defaults, configure the router minimally and manually (i.e. for testing, do not use a backup config file to configure the router after the full reset), and see if that fixes the issue.

[Wireless Router] When Standard Reset Isn’t Working: Hard Factory Reset - Models list | Official Support | ASUS USA

Use the link above (first, see important info below!) to use the appropriate reset method for your model.

Before you do the above, follow the steps below to get a baseline saved of where the router is at today. If doing the above doesn't solve your issue, then you can quickly get back to where you are now.

Is it a good idea to keep up with Firmware updates?

I have had issues in the past when updating firmware and Internet speed, But it may have just been a fluke, Should I keep up with the updates? If so On all routers or the nodes as well? What about ones acting as access points? Thanks

www.snbforums.com

 

[w_dolph]

Welcome to the forums @w_dolph.

The best/fastest way to troubleshoot this is to do a full reset to factory defaults, configure the router minimally and manually (i.e. for testing, do not use a backup config file to configure the router after the full reset), and see if that fixes the issue.

[Wireless Router] When Standard Reset Isn’t Working: Hard Factory Reset - Models list | Official Support | ASUS USA

Use the link above (first, see important info below!) to use the appropriate reset method for your model.

Before you do the above, follow the steps below to get a baseline saved of where the router is at today. If doing the above doesn't solve your issue, then you can quickly get back to where you are now.

Is it a good idea to keep up with Firmware updates?

I have had issues in the past when updating firmware and Internet speed, But it may have just been a fluke, Should I keep up with the updates? If so On all routers or the nodes as well? What about ones acting as access points? Thanks

www.snbforums.com

Thanks for swiftly getting back to me.

At the next most convenient time to do this, I'll do it and report back.

Just curious though, what's the general idea behind a factory reset going to fix? Some gummed up confused logic on the router or to "blank canvas" any settings that I may set incorrectly?

Going forward from here my general basic setup is: Seperate 2.4GHz & 5GHz bands, SSID names, WPA password. Is there anything that you may suggest I try outside of that after resetting?

(Also should add I don't use any of the optional tools such as AI Protection, AIMesh, Game Mode, QoS).

 

[sfx2000]

The 150mbps is the very rough average that the 2.4GHz devices get at common usage point of the house, it's not an optimal lay out, but that's not the issue here. At it's worst, I can hold my phone within 1m of the router and the speed would remain nearly unusable.

There's been other observations regarding AX capable devices and 2.4 - one thing to try is to disable 11ax/WiFi6 on the 2.4Ghz radios, and see where things go there...

 

[L&LD]

A factory reset allows the installed software to use the variables and defaults as it expects. 'Gummed up settings' from previous firmware is a good description. Also, note that toggling certain settings on/off isn't the same as leaving them off in the first place. Again, a full reset is the fastest way to a good/known state for your router/network.

You may find some of the following links helpful too.

Merlin on ASUS ax86U Question

I have an ASUS AX86U and contemplating the installation of Merlin firmware. The DDNS settings on the AX86U are limited to select dns providers. If I install Merlin, will I have more flexability (choices) with the DDNS Settings? Thanks in advance!

www.snbforums.com

Am I all set to start fresh with the latest stable release? And a request for L&LD...

After creating the checklists two weeks ago to save the pages with settings, I've made all the screenshots (I think at least) of all the relevant guides written by @L&LD and the very useful tip by @netware5. The only thing is, those guides are great, except when you'll be offline at least for a...

www.snbforums.com

L&LD

www.snbforums.com

 

[sfx2000]

A factory reset allows the installed software to use the variables and defaults as it expects. 'Gummed up settings' from previous firmware is a good description. Also, note that toggling certain settings on/off isn't the same as leaving them off in the first place. Again, a full reset is the fastest way to a good/known state for your router/network.

OP did not mention a restore from an older model - so we should probably treat this as a new install...

 

[L&LD]

No, he didn't. Depends on how much time he has to chase this wild turkey otherwise.

 

[Tech9]

Just curious though, what's the general idea behind a factory reset going to fix?

Recommended often on this forum when whoever replies to you has no idea what your problem really is. After you pay the welcome reset fee you may want to post your wireless settings and tell us what country are you in - then someone who knows how Wi-Fi works may start helping you.

 

[L&LD]

This has nothing to do with how WiFi works.

This has everything to do with being in a good/known state and then systematically eliminating if it's a hardware issue or something else.

You're welcome to waste someone else's time by guessing how WiFi works on a network that is known to be unstable.

I'm suggesting shortcutting altogether the guessing (and unknown interactions from the hardware and/or firmware) and getting right to real troubleshooting afterward.

When was the last time you turned on an Asus router? You know, the ones you don't use in your networks?

 

[Tech9]

@w_dolph, post screenshots with your wireless settings. Skip the guessing help offered.

You get 150Mbps on 2.4GHz to what client? Your router is perhaps attempting 40MHz wide channel, detects interference and switches back to 20MHz, later changes the channel to something else and the bandwidth chasing game continues. What is "5GHz band also suffers" in numbers and to what client?

With the limited information provided no one can help you and you can waste your time resetting your router forever.

 

[w_dolph]

Thanks for all of the replies thusfar.

Due to the network being depended on by other people than just myself, I need to wait for an oppurtune time to do the full fac. reset.

For the time being I went ahead and disabled the 11ax/WiFi6 on the 2.4GHz band as aforementioned by @sfx2000 as that is something that I could quickly toggle and test until a convenient time arrives for a fac reset. I wont really know for another 24 hours at least if this has had much of an effect so this post will be a slow process but I will commit to coming back and updating with information. (Don't want this to be one of those abandoned threads that might end up helping others too)

Appreciate the advice, I'm taking notes and will return with any notiable differences regarding the disabling of 11ax/WiFi6.

Edit: In regards to the other queries:

I'm in the UK, using Virgin as ISP via Hub5 in modem mode with a 1gbp Fibre package.

Those example numbers were from a phone and laptop in the same room specifically on the 2.4Ghz band.

'The 5Ghz band also suffers': I'll get in excess of 550mbps+ (up to 660mbps) on the 5GHz via phone on average, however when the 2.4ghz cripples to a hault, the 5GHz *can* go down to a noticable 150-300, however this is more inconsistent hence I didn't go into excess detail with this side of things. (Still more than usable but noticable difference).

Screenshots: Wireless & Wireless - Professional settings for both 2.4 & 5GHz. Aside from the obvious password, ssid name and aforementioned 11ax/wifi6 toggling off, I haven't touched the other settings, it is as default when setting up the router. If I leaked any sensitive information please let me know and I'll take it down.

In regrads to the factory reset, I will be aiming to do that within the next week - allowing some time for the 11ax/wifi6 quick-fix test to play out.

 

[L&LD]

How you're describing it now, this sounds like an ISP issue (over-promising, and under-provisioning), a local environment issue (neighbors, time of day, peak hours, etc., and/or local non-WiFi interference... are you close to shops/industrial parks?), or just normal congestion on the 2.4GHz band.

The phone 'results' should be discounted. Too many variables and power-saving features there to be useful.

The laptop should be plugged into AC power, and be on Performance mode (not Balanced or Power saving modes) to be doing a fair test. As should the WiFi card be checked that it is not allowed to go into power saving mode (at least, not while you're testing).

Creating a backup of your current configuration and resetting the router to full defaults won't take longer than 15 or 20 minutes from start to finish. The WiFi/internet will only be off for half that time at most. Don't see this as a chore. It is essential to know where you're starting from and what changes are actually needed to make a difference in your environment.

One of the first changes I would make is creating new SSIDs and/or passwords (at least while testing). This will ensure only you (and your authorized users) are testing the connection and not anyone else in the vicinity that may have gained access somehow.

 

[w_dolph]

How you're describing it now, this sounds like an ISP issue (over-promising, and under-provisioning), a local environment issue (neighbors, time of day, peak hours, etc., and/or local non-WiFi interference... are you close to shops/industrial parks?), or just normal congestion on the 2.4GHz band.

The phone 'results' should be discounted. Too many variables and power-saving features there to be useful.

The laptop should be plugged into AC power, and be on Performance mode (not Balanced or Power saving modes) to be doing a fair test. As should the WiFi card be checked that it is not allowed to go into power saving mode (at least, not while you're testing).

Creating a backup of your current configuration and resetting the router to full defaults won't take longer than 15 or 20 minutes from start to finish. The WiFi/internet will only be off for half that time at most. Don't see this as a chore. It is essential to know where you're starting from and what changes are actually needed to make a difference in your environment.

One of the first changes I would make is creating new SSIDs and/or passwords (at least while testing). This will ensure only you (and your authorized users) are testing the connection and not anyone else in the vicinity that may have gained access somehow.

Appreicate this.

While I'm not a networking expert, I can guarantee it's something with the router itself or the firmware/software on it.



Prior to using this router, I used the terrible VM Hub4 on router mode and that worked near flawlessly in terms of speed consistency / performance without ever needing a reset to restore speeds. (Can't say the same for it's power supply which died). This behaviour is definitely due to the GS-AX5400.

While I'm only mentioning a laptop and phone, I have a plethora of other devices (not always connected, spares/unused devices etc) that I would connect to the 2.4ghz to test out this slow down and they would ALL test around the same speeds (or ALL fail to even begin the speedtest).

Also as I believe I mentioned before, the WIRED connection stays 100% solid with the full expected speeds even when the 2.4GHz slows right down, suggesting that the bandwidth being piped down the line isn't being capped in anyway. Perhaps there's something I don't know about them being able to manage wifi bandwidth(?) though, I'm open to learning about this head scratcher.

I'm in what I'd call medium density residential & the ISP, House & Router/Modem location have been the same for 15+ years (Obviously not the same models but I'm talking about the physical layout). This behaviour is specifically when I introduced the GS-AX5400 into the mix.

However I'm not shutting down your advice, I will take everything into consideration and test one suggestion at a time allowing for several days for the problem to manifest (or hopefully not).

Thanks!

 

[sfx2000]

For the time being I went ahead and disabled the 11ax/WiFi6 on the 2.4GHz band as aforementioned by @sfx2000 as that is something that I could quickly toggle and test until a convenient time arrives for a fac reset. I wont really know for another 24 hours at least if this has had much of an effect so this post will be a slow process but I will commit to coming back and updating with information.

Sure - it's an easy enough test, and there are 2.4GHz devices out there that don't play well with the newer 802.11ax Beacon Frames...

Good luck with it, and looking forward to your updates

 

[Tech9]

I need to wait for an oppurtune time to do the full fac. reset

You don't need to rush with the reset. Specific forum members cure everything with reset. If it works for some unknown reason - victory, I told you. If it doesn't work - sorry, this is the best I can do for you. In both cases you don't know what your problem is or destroy valuable clues to resolution.

Lock 2.4GHz at Ch.6 and 20MHz - try again. In densely populated areas you can get 30-50Mbps max.
Disable AX, Roaming Assistant, all Beamforming, set modulation 802.11n, you can try disabling WMM APSD.

Lock 5GHz Ch.100 (if it works well for you) at 80MHz. You can get about 800Mbps to 2-stream AX client.
If Ch.100 is unstable select Ch.36* and test again. Disable Roaming Assistant and Universal Beamforming.

Your router on Auto is most likely bouncing between channels and switching between channel widths in never ending hunt for bandwidth. The more neighboring Wi-Fi networks you have the worse it gets. Your client devices may not be happy about frequent changes.

* - limited to 200mW Tx power in EU/UK, but in more guaranteed to work non-DFS range.

Look at System Log for something obvious - frequent channel change, frequent channel width change, DFS radar detection, etc. It's there to help. If you reset your router the logs are gone. If you continue on Auto the issue will perhaps return and you only waste your time.

 

[w_dolph]

Quick update while I have the time.

I've not been able to extensively test and closely monitor the speeds to due unforeseen circumstances.

However it's been 4 full days since I disabled the 11ax/WiFi 6 on the 2.4GHz band as mentioned earlier the post and so far the 2.4GHz band speeds are holding strong and maintaining expected speeds.

It's too early to deem this as a "fix" quite yet and I will continue to monitor the situation day by day. Should any changes happen I'll report back to this post, otherwise I'll set a reminder for two weeks from now to come back and hopefully declare a positively "fixed" result.

TLDR Summary:
Disabling 11ax/WiFi6 on 2.4GHz has seemingly addressed the issue. Will be reporting back after a longer more conclusive testing period.

 

[w_dolph]

There's been other observations regarding AX capable devices and 2.4 - one thing to try is to disable 11ax/WiFi6 on the 2.4Ghz radios, and see where things go there...

Two week update:

So it's been two weeks to the day since I made the single change as quoted above and I can happily report that all devices on the 2.4GHz band are still operating at full speeds without having to reboot the router once.

I even swapped over some devices that use 5GHz to the 2.4GHz band just to put it under a busy-ish load, did speedtests one by one on all devices and all achieved their expected max download speeds.

Also throughout the two weeks when I remembered, I was doing speed tests and different times of the day, different days and it all stayed within expectations.

It's not majorly scientific but I'm calling this a resolved fix. Hopefully this'll help others out there with the same issue. Should anything change I'll come back and use the other methods but so far @sfx2000 's fix is working perfectly. (hope I haven't jinxed it!)


Big thanks to everyone for their help, and special thanks to @sfx2000

 

[sfx2000]

It's not majorly scientific but I'm calling this a resolved fix. Hopefully this'll help others out there with the same issue. Should anything change I'll come back and use the other methods but so far @sfx2000 's fix is working perfectly. (hope I haven't jinxed it!)

remember, this is a short term workaround perhaps - as 11ax is supposed to be backwards compatible - that being said, in 2.4GHz, we moved from 11n past 11ac and straight into 11ax (which brings in features from both 11ac and 11ah) - so it's a big step for the 2.4GHz band...

Hopefully chipset firmware and drivers, mostly on the AP side as clients can go back 15 years or more for 11n - with updates things should get better...