Sporadic Wireless Connections?

[rljames]

Suddenly my RT-AC66U started exhibiting sporadic 2.4Ghz connections and 5Ghz disappeared completely. Everything I can think to check via the router Admin software seems OK, including absence of related Log messages. This occurred under v378.51 of ASUSwrt-Merlin firmware and upgrade to latest v378.54_2 did not solve the issues.

So, I'm wondering;

1. What are the symptoms of overheating? And what would be considered high router temperature?
   (Ambient in low 80F/75%RH, Router internal approaching 140F as reported via Router Admin -> Performance Tuning graph for radios)
   
   
2. What are the symptoms of nearby channel "competing" wireless devices? Is there a way to confirm/find this interference? And what AC66U setting(s) would minimize this potential issue?

Thanks,
Bob

 

[rljames]

If possible, I'd like to resurrect and hopefully escalate this thread.

Struggling with Wireless connections issues for some time now. Thought I'd upgrade to latest Merlin v378.55 but after reading the release thread it seems several Users reporting similar issues. I've tried to solve my particular puzzle with many experiments/solutions under my control and within my expertise. But no luck, and in fact appears to be getting worse...

So, I'm wondering if it might make sense for someone knowledgeable (Merlin?) to start a "sticky" thread and somehow aggregate meaningful "clues" to what might be going on with dropped wireless connections. Collect info such as; PC OS, Asus Router Model, Merlin FW version w/config changes to default, or any other data deemed potentially instrumental to the cause. I realize that there are many, MANY variables but maybe together we can find some sort of common cause pattern. Might actually discover the issue doesn't center around wireless at all but is some other router setting or outside the router cause.

Glad to help in any way I can but would warn that I'm by no stretch of any imagination a networking expert.

Thanks,
Bob

 

[joegreat]

So, I'm wondering if it might make sense for someone knowledgeable (Merlin?) to start a "sticky" thread and somehow aggregate meaningful "clues" to what might be going on with dropped wireless connections. Collect info such as; PC OS, Asus Router Model, Merlin FW version w/config changes to default, or any other data deemed potentially instrumental to the cause. I realize that there are many, MANY variables but maybe together we can find some sort of common cause pattern. Might actually discover the issue doesn't center around wireless at all but is some other router setting or outside the router cause.

Hi Bob,

Did you do the typical 3 debugging steps, like:
1) reset to factory defaults
2) minimal manual(!) configuration of the router/WLAN
3) testing the situation and try to provoke the issue to come?

On the other hands the issue came out of the blue (right?) and this points into two directions:
a) the router is getting faulty (yes, this devices can bite the dust out of a sudden )
b) your environment changed (the summer heat, other WLAN networks disturb your router, electricity supply and/or power adapter, etc.)

With kind regards
Joe

 

[rljames]

Joe,

Thanks for the reply and feedback. I'm stumped and really appreciate any help I can get...

Yeah, I've lived with the AC66U through several firmware upgrades and always follow conservative rules for upgrades with NVRAM reset and options reconfig even if not necessarily recommended. And I've re-flashed my current firmware more than once so I'm ruling out my upgrade procedures.

Also a retired software/firmware QA Engineer for products from medical devices to financial systems so I tend to follow fairly rigorous test methodologies.

And I did consider a new AC66U but when I began to read about others with similar problems I thought maybe the hardware was not at fault. So at this point, I think I'll leave that option to last resort.

Environment, in terms of network devices and changes is fairly stable but on the other hand it is Summer here and the temps can get a little warm. And in fact I raised that question in my original post. This could be another data point collected if we can put together some sort of collaborative diagnostic effort.

I also wonder about AC66U some settings such as "Wireless Mode -> b/g Protection" which tend to not have detailed explanation. Or any one of the other many config options?

Anyhow, I'll keep experimenting but I'm a novice and chasing my tail for lack of better info and direction. As of this writing, I've switched to cabled networking turned laptop wireless off. Let's see how this goes...

Thanks again,
Bob

 

[rljames]

OK, a little more information collected over the weekend -

1. Wireless 2Ghz connections repeatedly dropped to iPad and Android cellphone.
2. Wireless 5Ghz connection routinely disappears/reappears as Network Connection, iPad and Android.
3. Wired PC connection also drops but less frequently than wireless.

Conclusions -

1. Not a primary PC test bed network card issue due to problem also occurring on iPad and cellphone.
2. Not a competing Wireless device (eg. local Chromecast or neighborhood network) cause due to drop problem also occurring on wired connection.

Next test focus -

• Reduce ambient/AC66U temperature. Although I think general temperature is a low probability cause, reducing router temp is most likely a good idea regardless.

At this point, I'm wondering if the AC66U might be failing. But would like to somehow confirm before investing in a new router. And if problems do turn out to be flaky hardware, I'm already on my second AC66U and probably will switch away from ASUS...

Bob

 

[joegreat]

OK, a little more information collected over the weekend -

1. Wireless 2Ghz connections repeatedly dropped to iPad and Android cellphone.
2. Wireless 5Ghz connection routinely disappears/reappears as Network Connection, iPad and Android.
3. Wired PC connection also drops but less frequently than wireless.

Hi Bob,

The symptoms point to the 'beamforming' feature, which is often incompatible with iPhones and Android devices. Simply disable it under Wireless - Professional - for the two bands 2.4 GHz and 5 GHz (both settings: Explicit beamforming/802.11ac Beamforming and Universal Beamforming).
Reboot the router and 'forget' (=remove) the WLAN settings on your devices and re-connect fresh.

I had the same issues with .55 version update on my 68U router, but a factory reset (with manual re-config) helped to get the devices back to work.

Would be interesting to hear if this helps!

With kind regards
Joe

 

[TonyH]

Hi Bob,

The symptoms point to the 'beamforming' feature, which is often incompatible with iPhones and Android devices. Simply disable it under Wireless - Professional - for the two bands 2.4 GHz and 5 GHz (both settings: Explicit beamforming/802.11ac Beamforming and Universal Beamforming).
Reboot the router and 'forget' (=remove) the WLAN settings on your devices and re-connect fresh.

I had the same issues with .55 version update on my 68U router, but a factory reset (with manual re-config) helped to get the devices back to work.

Would be interesting to hear if this helps!

With kind regards
Joe

OP first mentioned temperature, why don't you take a temp. reading from router itself? Do you survey your neighborhood WiFi crowdiness if you suspect interference between channels? Trouble-shooting is step by step logical process, while you are on it, don't introduce other new things into process, like updating f/w, changing config., etc. complicating matters. Good luck.

 

[Calisro]

are you overclocked?

 

[rljames]

Hi Bob,

The symptoms point to the 'beamforming' feature, which is often incompatible with iPhones and Android devices. Simply disable it under Wireless - Professional - for the two bands 2.4 GHz and 5 GHz (both settings: Explicit beamforming/802.11ac Beamforming and Universal Beamforming).
Reboot the router and 'forget' (=remove) the WLAN settings on your devices and re-connect fresh.

Joe and others,

Thanks for taking the time to reply and offering feedback. I really appreciate the help and know how difficult it can be to diagnose something as complicated as a networking environment with so many variables

Just so the issue is clear - The original main problem is an ongoing sporadic wireless connection of AC66U to Laptop. Although use of iPad, cellphone, other devices is important, I added info on the stability of their connection to router testing primarily to determine if the PC was as fault. Since they also show connection drops, I can reasonably conclude that PC NIC etc is OK.

And using the PC via Ethernet cable direct to router where connections also drop suggest that it's not simply or solely a wireless issue. This conclusion is less clear since the wired drops are much less frequent.

As for "beamforming" settings as the possible cause. I think this illustrates part of the problem with resolving various performance issues - My AC66U v378.54_2 "Wireless -> Professional" settings page offers 20 some options, none of them contain the word "beamforming" and most have very limited superficial info on what they actually do/control. The point here is, although the AC66U may a great router with terrific Merlin firmware, it's difficult to use/setup effectively when meaningful documentation for so many config options is lacking.

For instance on Settings - On the basic "Wireless -> General" page, I'm not even entirely sure what is the proper "Channel Bandwidth" setting and why. Anyhow, as I mentioned above, I'll solve the iPad and Android issues once PC problems are solved and understood.

I routinely survey the bands in my relatively crowded neighborhood. Usually all channels are equally busy and I typically leave the router "Control Channel = Auto" for both bands. This setting has been maintained consistently through other firmware releases that seemed stable. Again, not exactly sure how any of the settings should be configured but try to stay consistent across firmware installs.
At one point, inSSIDer utility data suggested that perhaps my Chromecast was the culprit but have eliminated that possibility by removing device from the network and connection drop problems continue.
The AC66U is not overclocked.

I am the original June poster and the current testing focus returns to temperature. Yesterday, I took the time to remove AC66U cover and check what I could on circuit board for heat sink seating, other loose connections, dust etc. Also bought a fan. Today I'll use the PC wirelessly connected to cover-less router cooled by fan and record performance/temps.

Quick first temps look -

• AC66U with cover about 140 degrees F for both bands.
• Without cover - 120 F.
• Without cover and fan - approx 110 F.
• (Outside temps yesterday almost 90 F and PC office around 80 F)

Bob

 

[rljames]

Just a quick update, in case anyone is interested in my connection troubles and related cause experiments;

After a few relatively substantial wireless 2GHz PC to Router activity days, Office temps around 80 F -

AC66U cover Off, Fan On

2Ghz @ ~115 F, 5GHz @ ~117 F - No connection drops​

AC66U cover Off, Fan Off

2GHz @ ~127 F, 5GHz @ ~130 F - No connection drops​

Added a couple 5Ghz clients (iPad & Android phone) -
AC66U cover Off, Fan Off

2GHz @ ~127 F, 5GHz @ ~137 F - No connection drops​

Next I'm thinking of upgrading to latest Merlin v378.55 firmware and then if stable, adding back various wireless clients.

 

[ColinTaylor]

I think the key piece of information is that you say the PC's wired connection also drops. It doesn't matter whether it's less frequent or not. It points to an overall problem with the router (or the connections to it) and means that any wireless issues you have are supplementary.

Solve the wired PC problem first and then see if you still have wireless issues.

So, when you say that the PC connection "drops" what exactly do you mean? Does your PC show that its network adapter is in a disconnected state? If so then that would suggest a hardware issue.

Or does the network connection stay active but you just can't get to the internet? if so, can you get to the router's GUI, which would imply a problem with you ISP connection.

If you can answer these questions you can start to narrow down the problem. (My gut feeling is that it's overheating though)

 

[sfx2000]

I think the key piece of information is that you say the PC's wired connection also drops. It doesn't matter whether it's less frequent or not. It points to an overall problem with the router (or the connections to it) and means that any wireless issues you have are supplementary.

Seems like this might be a power problem - check the wall adapter, intermittent drops are a key sign that they're going "soft" - voltage will drop on higher current draw based on activity.

 

[Wisiwyg]

Seems like this might be a power problem - check the wall adapter, intermittent drops are a key sign that they're going "soft" - voltage will drop on higher current draw based on activity.

This!
Most of the problems I've had with wifi/routers and cable modems is the little wall warts supplied with the device. Those things are notoriously of poor quality - cheapest bidder - and just barely meet specs when new. Give them a few hundred hours of heat and they start to fail, but not all of the sudden - which would be easy to diagnose. Noooo, they fail slowly, dropping out, then coming back in, making a simple troubleshooting difficult. You either have to put a meter on them or swap out a known good wart. I keep a couple of the more common types on-hand for this reason, usually spec'd with excess power capacity. Saved me headaches more than once.

 

[rljames]

I think the key piece of information is that you say the PC's wired connection also drops.

I agree, the wired drop might be a big clue but also somewhat confusing since it occurred literally once in contrast to wireless which can happen several times in 10 minutes. And my definition of "drop" is when the PC reports "Internet Not Found" error and either wired or wireless link to router is lost. Generally, waiting long enough will auto reestablish the connection.

At this point, with AC66U cover off and router temps typically in the 125 to 135 F range, everything has been very stable and performing quite well for a few days. Not a single drop and could be my imagination but overall speed actually feels much better than usual.

Current plan is to evaluate with cover off for at least a week. Would like to update firmware to latest v378.55 but might just wait for .55_x maintenance release.

 

[DaBiGoReO]

Looks like the AC66U uses the same exact chassis/shell as the N66U which imho has a piss poor design when it comes to thermal/heat management. Whoever decided at Asus that vent holes were not needed on the top cover of a BLACK housing with a passive, seriously inadequate bridged heatsink on the radios was a true genius <sarcasm off>.

I am toying with removing that heatsink and replacing it with separate copper units for better heat dissipation. In the meantime, I have modified my top cover with a vent hole pattern to allow the case to breathe better. Just removing the top cover dropped temps by 5-6C which is a big difference. My previous N16, which was nowhere near as powerful as the N66, got pretty toasty until I replaced the heatsinks on that. Funny thing is, that router had vent holes on the top cover!

 

[Calisro]

isnt 137 degrees F pretty cool for a router? Isn't TJMAX on the things in the 130+ degree C?

Even the 5ghz and 2.4 temps @ 58 C (137 F) isnt very high....

 

[rljames]

isnt 137 degrees F pretty cool for a router?

I don't know if 137 F is cool for a router and the AC66U is ugly w/o the cover but my connection issues have clearly and completely stopped. At this point, I'm thinking of drilling a few strategically placed holes in the cover and putting it back on. Ideally I'd like to force temps up and if problems reoccur confirm heat as the cause but I'l most likely save that experiment for another day - Right now, I'd like to get network relatively back to "normal"...

 

[kvic]

Look at this video. Kind of cool..too bad the turbojet-alike can't make the router fly faster than its clock. lol

Seriously I think adding a small low-RPM fan (40x40x10 5V USB powered) is more effective than a few holes. Mount the fan below the label on its back. Blow into the case. Your AC66U will be cool and stable for as long as you wish.

 

[kricker]

I have noticed similar issues with my 2.4 ghz wireless. The 2.4 ghz would actually turn off and then back on again repeatedly. It just started randomly. After trying multiple resets and wireless settings it kept happening. Finally one last ditch attempt I turned off wireless protection settings and left the 2.4 ghz signal open. Since then the 2.4 ghz wireless has not turned off once.

 

[rljames]

I turned off wireless protection settings and left the 2.4 ghz signal open. Since then the 2.4 ghz wireless has not turned off once.

IMHO, the "b/g Protection" setting is one of those router firmware options that doesn't have a lot of detailed documentation. Context Help for the "Wireless Mode" label suggests that "router workload" is increased when "b/g Protection" is activated. But not much other info is given.

What devices might need "Protection" enabled?
What exactly does the router do when the option is turned on?