Speed drops on RT-AC56U - from gigabit to 100mbps and incredibly poor speeds

[TheImmortal]

I use the router in AP mode and, for a couple of months now, I noticed the speeds suddenly dropping to 100mbps, using various forks made by John from the Merlin builds. Usually, a unplug/plug or reboot would fix it, but the issue would appear days after. WiFi speeds equally crappy.

Now i've updated the firmware, speeds to my desktop are top notch (800mbps to gigabit), however the wireless devices see an abysmal 2 to 10mbps.

Anyone happen to know what this is due? Is the router begging me to be replaced, is a cable damaged - but, if it is, why is wifi so poor? The chromecast, 3meters away, was yesterday reaching 250mbps, now i can't get it past 8mbps, even though my desktop gets the full gigabit? What log is there that could maybe provide some insight?


Thank you.

 

[OzarkEdge]

I use the router in AP mode and, for a couple of months now, I noticed the speeds suddenly dropping to 100mbps, using various forks made by John from the Merlin builds. Usually, a unplug/plug or reboot would fix it, but the issue would appear days after. WiFi speeds equally crappy.

Now i've updated the firmware, speeds to my desktop are top notch (800mbps to gigabit), however the wireless devices see an abysmal 2 to 10mbps.

Anyone happen to know what this is due? Is the router begging me to be replaced, is a cable damaged - but, if it is, why is wifi so poor? The chromecast, 3meters away, was yesterday reaching 250mbps, now i can't get it past 8mbps, even though my desktop gets the full gigabit? What log is there that could maybe provide some insight?


Thank you.

Do you have WiFi interference? Have you tried different channels? Are the antennas on tight? Do the signals appears strong and stable on a WiFi Analyzer app? Are you resetting the firmware before configuring it from scratch?

OE

 

[TheImmortal]

The channels seem set to auto, but they'd have no impact over to 'gigabit to 100mbps' vlan speeds :/ The chromecast, for example, only jumped back to 150mbps AFTER restarting the device, which i find baffling.

I do not reset the device nor reconfigure it prior to firmware updates - i use sambas and have quite a few modifs that i don't fancy re-doing; the configs, however, worked perfectly fine for years :"/

 

[OzarkEdge]

I do not reset the device nor reconfigure it prior to firmware updates - i use sambas and have quite a few modifs that i don't fancy re-doing; the configs, however, worked perfectly fine for years :"/

The question was, are you resetting the firmware before configuring it?

Apparently not.

Here's some suggested reading:

Reset FAQ
Reset Button/webUI Restore
WPS Button Hard Reset

Further troubleshooting is pointless without confirming the firmware is properly installed and commissioned.

OE

 

[Zetto]

I think with old routers next thing to try is swapping out the power adapter, they are quite prone to failure.

 

[TheImmortal]

syslog is naked when it comes to these failures, it baffles me how such serious change wouldn't be logged. I'll try factory restoring later today, though in all fairness, i've never done more than clearing the nvram, whilst these issues go only 2months or so back.

 

[OzarkEdge]

syslog is naked when it comes to these failures, it baffles me how such serious change wouldn't be logged. I'll try factory restoring later today, though in all fairness, i've never done more than clearing the nvram, whilst these issues go only 2months or so back.

To be honest, we don't know what the issue it.

We do know that you have used multiple different firmware and have never install them as is recommended... because it's not convenient. So, that would be the place to start your troubleshooting... unless you have a better idea.

OE

 

[TheImmortal]

I got it. It sounds to me like we won't know what the issue is after the reset either, since it still won't log anything, but at least we had things done a certain way. I'm going to have the nvram wiped right now and ALL the internals reconfigured because im excited to hear what solutions I'll get once this reoccurs.

 

[OzarkEdge]

I got it. It sounds to me like we won't know what the issue is after the reset either, since it still won't log anything, but at least we had things done a certain way. I'm going to have the nvram wiped right now and ALL the internals reconfigured because im excited to hear what solutions I'll get once this reoccurs.

It's good to be motivated. Once the firmware concern is addressed, we'll be more motivate to think about other possible issues, if any remain.

OE

 

[TheImmortal]

Ok, i think i'm all set (helps having screenshots of all tabs, i guess) - my main concern was for devices to maintain their internal IPs, which appears to have happened. I've been booted DIRECTLY to a 100mbps connection, so idk...i really dont. Wifi obviously sucks (20mbps tops).

All im seeing and that might be related are these:

Mar  5 17:35:40 kernel: br0: port 3(eth2) entering forwarding state
Mar  5 17:35:40 kernel: br0: port 2(eth1) entering forwarding state
Mar  5 17:35:40 kernel: br0: port 1(vlan1) entering forwarding state
Mar  5 17:35:40 kernel: br0: port 1(vlan1) entering disabled state
Mar  5 17:35:40 kernel: br0: port 2(eth1) entering disabled state
Mar  5 17:35:40 kernel: br0: port 3(eth2) entering disabled state
Mar  5 17:35:40 kernel: br0: port 3(eth2) entering forwarding state
Mar  5 17:35:40 kernel: br0: port 3(eth2) entering forwarding state
Mar  5 17:35:40 kernel: br0: port 2(eth1) entering forwarding state
Mar  5 17:35:40 kernel: br0: port 2(eth1) entering forwarding state
Mar  5 17:35:40 kernel: br0: port 1(vlan1) entering forwarding state
Mar  5 17:35:40 kernel: br0: port 1(vlan1) entering forwarding state
Mar  5 17:37:54 kernel: br0: port 2(eth1) entering forwarding state
Mar  5 17:37:54 kernel: br0: port 3(eth2) entering forwarding state
Mar  5 17:37:55 kernel: br0: port 2(eth1) entering forwarding state
Mar  5 17:37:55 kernel: br0: port 2(eth1) entering forwarding state
Mar  5 17:37:55 kernel: br0: port 3(eth2) entering forwarding state
Mar  5 17:37:55 kernel: br0: port 3(eth2) entering forwarding state

LE: rebooted the router...still 95-96Mbps tops on fast.com. Removed and reseated the cables - gigabit on desktop, but wifi remains absolutely atrocious - 9Mbps on my phone, next to the router, 8Mbps on my chromecast (~4meters away). After re-establishing the connection to the chromecast, this now works at 107Mbps.

I see that my cellphone is connected on the 2.4Ghz band, which would explain it - i guess the chromecast is doing this too? I keep both 2.4 and 5 with the same SSID since i have an older generation laptop, so now likely the issue is 'why does it drop from 5ghz to 2.4ghz'. Even when i reconnect, still 2.4Ghz, even though i set 5Ghz in wireless-> general. I'm literally looking at my P30 pro re-establishing the wifi and picking 2.4ghz, 'good' signal, 13Mbps speed at...20cms away from the router.

 

[OzarkEdge]

Ok, i think i'm all set (helps having screenshots of all tabs, i guess) - my main concern was for devices to maintain their internal IPs, which appears to have happened. I've been booted DIRECTLY to a 100mbps connection, so idk...i really dont. Wifi obviously sucks (20mbps tops).

All im seeing and that might be related are these:

Mar  5 17:35:40 kernel: br0: port 3(eth2) entering forwarding state
Mar  5 17:35:40 kernel: br0: port 2(eth1) entering forwarding state
Mar  5 17:35:40 kernel: br0: port 1(vlan1) entering forwarding state
Mar  5 17:35:40 kernel: br0: port 1(vlan1) entering disabled state
Mar  5 17:35:40 kernel: br0: port 2(eth1) entering disabled state
Mar  5 17:35:40 kernel: br0: port 3(eth2) entering disabled state
Mar  5 17:35:40 kernel: br0: port 3(eth2) entering forwarding state
Mar  5 17:35:40 kernel: br0: port 3(eth2) entering forwarding state
Mar  5 17:35:40 kernel: br0: port 2(eth1) entering forwarding state
Mar  5 17:35:40 kernel: br0: port 2(eth1) entering forwarding state
Mar  5 17:35:40 kernel: br0: port 1(vlan1) entering forwarding state
Mar  5 17:35:40 kernel: br0: port 1(vlan1) entering forwarding state
Mar  5 17:37:54 kernel: br0: port 2(eth1) entering forwarding state
Mar  5 17:37:54 kernel: br0: port 3(eth2) entering forwarding state
Mar  5 17:37:55 kernel: br0: port 2(eth1) entering forwarding state
Mar  5 17:37:55 kernel: br0: port 2(eth1) entering forwarding state
Mar  5 17:37:55 kernel: br0: port 3(eth2) entering forwarding state
Mar  5 17:37:55 kernel: br0: port 3(eth2) entering forwarding state

LE: rebooted the router...still 95-96Mbps tops on fast.com. Removed and reseated the cables - gigabit on desktop, but wifi remains absolutely atrocious - 9Mbps on my phone, next to the router, 8Mbps on my chromecast (~4meters away). After re-establishing the connection to the chromecast, this now works at 107Mbps.

I see that my cellphone is connected on the 2.4Ghz band, which would explain it - i guess the chromecast is doing this too? I keep both 2.4 and 5 with the same SSID since i have an older generation laptop, so now likely the issue is 'why does it drop from 5ghz to 2.4ghz'. Even when i reconnect, still 2.4Ghz, even though i set 5Ghz in wireless-> general. I'm literally looking at my P30 pro re-establishing the wifi and picking 2.4ghz, 'good' signal, 13Mbps speed at...20cms away from the router.

Could be a dying radio.

I would try different fixed channels in case there is some interference coming from somewhere, either other WiFi or some other radio device.

I'm not familiar with using vlans.

OE

 

[OzarkEdge]

I see that my cellphone is connected on the 2.4Ghz band, which would explain it - i guess the chromecast is doing this too? I keep both 2.4 and 5 with the same SSID since i have an older generation laptop, so now likely the issue is 'why does it drop from 5ghz to 2.4ghz'. Even when i reconnect, still 2.4Ghz, even though i set 5Ghz in wireless-> general. I'm literally looking at my P30 pro re-establishing the wifi and picking 2.4ghz, 'good' signal, 13Mbps speed at...20cms away from the router.

Look at your signals with a WiFi Analyzer app... are they strong and stable?

OE

 

[TheImmortal]

the app doesn't do anything on my phone, but (pause for effect)...

yet another reboot, this time on my phone, does. the phone now is finally getting the 5Ghz freq (i reconnected it at least a dozen times), link speed at 150Mbps-ish and excellent signal. Wth is going on with this need for reboots...Argh.

 

[OzarkEdge]

the app doesn't do anything on my phone, but (pause for effect)...

yet another reboot, this time on my phone, does. the phone now is finally getting the 5Ghz freq (i reconnected it at least a dozen times), link speed at 150Mbps-ish and excellent signal. Wth is going on with this need for reboots...Argh.

Are you getting similar results with various 'test' devices? I prefer using a trusted PC vs a mobile device.

OE

 

[TheImmortal]

I'll have this updated if (...when?) I notice my desktop's speed dropping to 100Mbps. Right now...all looks fine and dandy.

 

[OzarkEdge]

I'll have this updated if (...when?) I notice my desktop's speed dropping to 100Mbps. Right now...all looks fine and dandy.

Allow some time for a new network to settle down before hammering on it or layering on accessory features... get to know it first to build your trust in it.

OE

 

[TheImmortal]

Today i woke up to have the WAN at 100mbps in sysinfo and lighting green (good thing about the reset...i forgot it had leds!); had to re-seat the cable inside the socket (it does feel as if the socket is a bit loose? That socket is what I previously blamed and ended up changing 3 rj45 jacks until i got to pe perfectly sure it's all rite.

Now it's either the cable or the router's WAN port. And in all fairness, it'd be easier to change the router than the cabling :/ But i guess i'll have to try another cable?

Just slightly wiggling the cable while in socket gets the light back to green or even no light, prompting the port to be down/100mbps....wtf? 4 RJ45 jacks already for this same issue, i swear the cabling in it is correct...

 

[OzarkEdge]

Today i woke up to have the WAN at 100mbps in sysinfo and lighting green (good thing about the reset...i forgot it had leds!); had to re-seat the cable inside the socket (it does feel as if the socket is a bit loose? That socket is what I previously blamed and ended up changing 3 rj45 jacks until i got to pe perfectly sure it's all rite.

Now it's either the cable or the router's WAN port. And in all fairness, it'd be easier to change the router than the cabling :/ But i guess i'll have to try another cable?

Just slightly wiggling the cable while in socket gets the light back to green or even no light, prompting the port to be down/100mbps....wtf? 4 RJ45 jacks already for this same issue, i swear the cabling in it is correct...

Sound like you have hardware issues. Nothing that spending a little money can't fix.

OE

 

[dlandiss]

4 RJ45 jacks already for this same issue, i swear the cabling in it is correct...

Get a can of compressed air and blow the cat hair out of the jacks...

 

[TheImmortal]

I switched the cable from the WAN port to LAN4 (since it's in AP mode, i can do that heh) - looks much better now, so could be the port. I wiggled & jiggled and pulled the cable and the connection remained at gigabit. I'll keep on checking this and update if the issue reoccurs (if so, i plan to test moving the ac56u near the ONT, use another cable and check the stability/resistance on the same ports, before replacing the cable). It does seem like I now, at least, have a plan to correect these.

Appreciate the help!