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Any known issues regarding AC2900/RT-AC86U 2.4 GHz radio malfunction?

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My 2.4 rock solid here.

2.4 settings:
Channel width manually set to 20 MHz.
Mu-MIMO disable.
Universal Beamforming disable.
Airtime fairness disable.
Roaming assistant disable.
Reduce USB 3 interference disable.

All these have been recommended at one time or another in this forum.
Might be worth trying?

I followed with above settings, unfortunately with same results as previously. After approx. 6h 2.4 WiFi becames unstable-innitialy a part of my devices have disconected and then they connect again but link is 6/6 Mbps...

Today I am going do downgrade further to 383...
 
Hey guys,

First post here (done plenty of reading -- hopefully enough). Around 2 weeks ago I replaced my older RT-AC1900/AC68U router with a new AC2900/RT-AC86U router and immediately flashed the latest stock firmware followed by Merlin's latest (384.4_2). The behavior I encountered was rather bizarre: after some arbitrary amount of time, the 2.4 GHz radio would stop broadcasting, and all clients would disconnect. Occasionally it would come back, but thereafter, no intranetwork access between clients was possible (only internet connectivity -- that's it).

I tried resetting to factory defaults, reflashing multiple firmwares (including the stock ASUS firmware for a few days), but the problem persisted. Today I'm returning the device as I'm fairly convinced that it (hopefully) may be a hardware issue. Radio temps were in the 40s and CPU was in the 70s C if that's of any assistance to anyone (but my 68U runs at 50s/80s constantly, so I doubt it's heat-related).

My question is: does anyone else have experience with this sort of behavior from this unit? I run a tech consulting company from my home and I really do need rock-solid operation, which my RT-AC68U has been giving me for years now (I just wanted a stronger 5 GHz signal, hence the upgrade). Should I simply replace it with another AC2900/RT-AC86U and expect better results from the next one?

FYI, my RT-AC68U is running 380.70 Merlin. I'm a little bit afraid to make the jump to the newer branch thanks to the consistency I've seen out of 380 and below. Maybe someone can set my mind at ease there as well ;-)

Thanks so much for any insight!

See if this post helps

[Beta 384/NG] Asuswrt-Merlin 384.5 Beta is now available
https://r.tapatalk.com/shareLink?sh...rums.com/index.php?posts/403103/&share_type=t
 
Try these settings.

Wireless 2.4 GHz Professional
Turbo QAM - Disable (Only helps with clients that support it and there are not very many)
Airtime Fairness - Disable
Multi-User MIMO - Disable (FWIW I got better 5 GHz speeds with MU-MIMO disabled)
Explicit Beamforming - Disable
Universal Beamforming - Disable
Reducing USB 3.0 interference - Enable (Enabling this feature ensures the best wireless performance on 2.4 GHz band)

I have 10 clients on my 2.4 GHz band. Some of them didn't like channels 1 and 6 but are happy on 11 so it may be worth trying different channels. Perhaps there is one problem client that is ruining the party for everyone else. I would start with one client and slowly add clients one at a time to see if a particular client brings down the radio.
 
tonight another wifi problems occured.
now even flashing fresh firmware (merlin stable, merlin beta, asus stable) does not provide to fixing the 2.4g radio unstability...


couple days ago, when the same problem apperaed, it was enought to flash 284.2_2 again and make a long power cycle. Now it does not work at all.

maybe some part of these routers are broken out-of-box?
 
AC-3100 here, I came across this same issue running previous versions of the 384 firmware. Haven't tried any builds in the past month or two, but everything runs rock solid on the older 380 firmware. Glad to see I'm not alone in this problem. Same issue though - after a few hours, the 2.4 band would just become incredibly slow and/or unreliable for all devices connected to it (5.0 band seemed just fine). Just wanted to throw my two cents out there that this might not be limited to just the AC68U.
 
I've had similar issues with my AC86U and R7000.

I resolved my issues yesterday, it was my Nvidia Shield TV that was acting as a WIFI jammer on only the 2.4G. Not sure what caused it but I blame an app that was supposed to be able to handle the BT connections that I bought from the Play Store. I noticed that it reported unknown BT and WIFI in device settings.
When it was on I got "Wrong password", "Can't connect" or the WIFI just missing on the 2.4G, 5G has been working all along.
At other times it was just working for internet but not for LAN access, and generally devecies came on and off.

After a restore on the Shield the WIFI has been working fine for two days (new record). EDIT: 5+ days.
I had the same problem with my previous router R7000 XWRT, that was the reason I bought the AC86U. I've been having this problem for quite some time. I found it by turning on one more device every 24h.

EDIT: It turned out that I had two problems, one was the nVidia Shield’s USB3 and the other was this issue with the 2.4GHz band on AC86U.
 
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Can’t figure out which device working problematically, but already noticed more stable 2.4 WiFi when legacy mode is chosen at 2.4 wireless settings page.

When switched back to N mode or automatic- majority of my devices are able to reach only 5.5 mBits.
 
I upgraded a N66U (which has been rock solid) to a AC86U 3 weeks ago. It worked perfectly for 2 weeks on the latest ASUS firmware. Then all of a sudden, all the 2.4 clients dropped out with auth failures and those that could switched to 5GHz. I reset to factory defaults but no luck with 2.4. My Pixel 2 phone would appear to connect but when I would try to get any data from the Internet, it would drop. Previously the phone worked well on 2.4 with a speed of 70Mbs or so download. The phone was fine on 5.

Because my time to return it was closing at Amazon I did not have a lot of time to fool with it, I returned the router for a refund and reluctantly went back to the N66U which does not have the range the AC86U had. My assumption was this was some hardware issue and I debated on getting a replacement instead of a refund. Now after reading all this, I think I will wait a bit before taking a chance on this router again. It was a great router while it worked.

How is it that a device can work perfectly for 2 weeks and then just quit when nothing has changed? Oh well.
 
I upgraded a N66U (which has been rock solid) to a AC86U 3 weeks ago. It worked perfectly for 2 weeks on the latest ASUS firmware. Then all of a sudden, all the 2.4 clients dropped out with auth failures and those that could switched to 5GHz. I reset to factory defaults but no luck with 2.4. My Pixel 2 phone would appear to connect but when I would try to get any data from the Internet, it would drop. Previously the phone worked well on 2.4 with a speed of 70Mbs or so download. The phone was fine on 5.

Because my time to return it was closing at Amazon I did not have a lot of time to fool with it, I returned the router for a refund and reluctantly went back to the N66U which does not have the range the AC86U had. My assumption was this was some hardware issue and I debated on getting a replacement instead of a refund. Now after reading all this, I think I will wait a bit before taking a chance on this router again. It was a great router while it worked.

How is it that a device can work perfectly for 2 weeks and then just quit when nothing has changed? Oh well.
I just decided to replace my unit because there are also lots of possitive feedbacks. We will see what happen.

Wysłane z mojego LG-H870 przy użyciu Tapatalka
 
Just a progress report as promised:

After making the previously-detailed/prescribed changes, I've been running the router in my environment without any reboots or modifications since my last post here (10 days ago) and have not yet experienced any issues. Nothing else has changed (and I still have a ton of clients connected -- for the most part, nothing on that end has changed).

So perhaps, hopefully, the solution lies in either 384.3 or one of the settings adjustments that was recommended (or perhaps both). I'd recommend everyone try my exact configuration before giving up on the situation.

Hopefully whatever is wrong can be corrected in future firmware revisions. It seems very likely we have a valid bug on our hands here.
 
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which recommended adjustment you meant?

edit:
G3DMGpp.jpg

vzdoXNV

after dirty downgrade via VPN and set recommended adjustments my wifi works again but rx rates are very slow.
volumio(raspberry pi) which should reach 72/72 Mbps looks strange.
I am going to try initialization when come back to my flat.
 
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which recommended adjustment you meant?

edit:
G3DMGpp.jpg

vzdoXNV

after dirty downgrade via VPN and set recommended adjustments my wifi works again but rx rates are very slow.
volumio(raspberry pi) which should reach 72/72 Mbps looks strange.
I am going to try initialization when come back to my flat.

Here's my quote from earlier explaining what I changed:

[Runnng 384.3]: 2.4 GHz channel width is still set to 20 MHz; the only other thing I've done differently this time is to disable MU-MIMO and enable Reducing USB 3.0 interference on 2.4 GHz as well. We shall see what results.
 
Another update:

Still running stable today, some two weeks later. It seems quite likely that the solution to these problems is to flash 384.3 and adjust the settings as I did (per advice here in this thread). Something appears to be wrong with all future versions of the firmware for now.

I'd advise anyone else experiencing these issues to try the same steps... and report back so the community can hear about the results!
 
I forgot to report:

I tried almost every single version of firmware, stock and Asus Merlin with no luck.
My devices sometimes connect normalny but link rates are very low, another time they are unable to connect because of „authentication failure”.

I checked all parameters of WiFi to be adjustable...there are no solution to my Asus.

Meanwhile i bought synology rt2600ac to check that router itself and also check possible interferences in my flat. Fortunately synology works perfectly. Nonetheless i love Asus Merlin and its advantages and want to 86u again. Simultanously I am affraid to experience The same problems again....perhaps i Should wait for next revision of rt-ac86 because The number of negative reports is suspicious.
 
I forgot to report:

I tried almost every single version of firmware, stock and Asus Merlin with no luck.
My devices sometimes connect normalny but link rates are very low, another time they are unable to connect because of „authentication failure”.

I checked all parameters of WiFi to be adjustable...there are no solution to my Asus.

Meanwhile i bought synology rt2600ac to check that router itself and also check possible interferences in my flat. Fortunately synology works perfectly. Nonetheless i love Asus Merlin and its advantages and want to 86u again. Simultanously I am affraid to experience The same problems again....perhaps i Should wait for next revision of rt-ac86 because The number of negative reports is suspicious.

Thank you for your updates! I have been putting off updating my AC3100 to 384.5 due to having issues in the past with this problem. Hopefully things will be different this time around.
 
I had a lot of issues with 2.4ghz on my ac88u. I turned on debug level logging and found out that a few devices on 2.4ghz kept asking for dhcp reservations affecting only 2.4ghz band. Turn on debug level logging and see if you are getting something like this. After moving the devices thad exhibited the dhcp issue over and over, the 2.4ghz had been rock solid.
 
Would anyone be so kind to explain to some of us newbies the difference between "Restore" and "Initialize" functions? I thought I was to always do a Restore when flashing from one FW version to another and then re-enter all info from scratch but frankly I am not familiar with what Initialize does.

Thank you!
 
Would anyone be so kind to explain to some of us newbies the difference between "Restore" and "Initialize" functions? I thought I was to always do a Restore when flashing from one FW version to another and then re-enter all info from scratch but frankly I am not familiar with what Initialize does.

Thank you!

Now I'm wondering if I've been doing it wrong as well. I've always updated the firmware, reboot, and then do a factory default/reset, reboot again, and then manually set everything up again.
 

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