Disappointed with 2.4GHz band performance

[kpiontek]

Hi everybody,

I just got a RT-N66U (rev B1, manufactured in 2013) to replace an aging WNDR3700 rev1 used as an AP (being on FIOS). The WNDR3700 was rock solid in 24/7 operation for a few years, but started recently to occasionally drop/refuse connections, so I thought with a decent deal on the RT-N66U to simply replace the old one before it completely drops out.
I had read the reviews here in the forum and saw the great support this router received including Merlin's firmware and thought it would be a great choice. So I immediately uploaded the most recent Merlin firmware (RT-N66U_3.0.0.4_372.30_3 for all versions), cleared the NVRAM, and set the same parameters as the old AP, including the same channel in the crowded 2.4GHz band to avoid interference with nearby wireless APs. The performance in the 5GHz band was great, better than it ever was with the old one, but the same could not be said about the 2.4GHz band. While it seemed initially to work, a short while later it completely dropped all connections. It was impossible to connect with any laptop, tablet, smartphone etc. I erased the NVRAM again, just in case, and after setting SSIDs and channels as before, a similar thing happened, this time the connections on 2.4GHz were not dropped but were very slow (5-24 Mbps) with excellent signal quality reported and even when close to the router. Made no sense.
Upgraded to the newest firmware from Asus (3.0.0.4.372.1393) and while the 5GHz band wasn't as good the 2.4GHz band seemed initially been fixed. Seemed is the keyword, as a day later I observe the same slow connections with all devices (tablet, laptop etc). I used speedtest.net to test the connection speed in "real life" and I get 2-5 Mbps speed (FIOS service is 75/35 Mbps) and when I change to the 5GHz band on the laptop for example the speeds shoot up to about 65/30 Mbps, about what you would expect (speed in Intel PROset is reported as 150-216 Mbps). It simply confirms the noticed slow speed like loading websites or downloads.
Before sending this thing back, I'd like to try some suggestions from this forum, including older Merlin firmware or changing transmission power from the default of 80 mW that might fix the 2.4GHz issue (unless it's a hardware defect, which could be the case). I have attached the insider screenshot to show the wireless signals in the neighborhood.
So hopefully someone has suggestions that I could try.

Thanks.

Klaus

 

[soapy]

have had so many problems with this router and firmware, i eventually tried merlins 3.0.0.4 270 26b and found it to be the most stable so i would recommend you try that version, i had problems with the 2.4ghz band not putting enough power out but it seems good now with that firmware

 

[sm00thpapa]

I have had this router for a little over a year now and the 2.4 GHz band has been rock solid no matter what firmware I used. On the other hand the 5 GHz band has had problems once .370 and .372 was released. I'm sticking with .271 for now. I have tried Merlins .270.26b and his .372.30_3. They work well but a few times the 5 GHz band went out and I can't stand on the network page that it just keeps loading with no results. This router has got me fed up and I will be looking for another brand router with AC band soon.

 

[jlake]

Try removing your old wireless profiles.


http://kb.linksys.com/Linksys/GetAr...less_Network_Profiles_.xml&pid=80&converted=0

 

[jim769]

Sounds like interference to me the rt-n66u has such great antennas that it seems to pick up more then other routers do. That is great for sending the signals out but also means it sees more nearby routers and more interference from them. Just a thought because I know the 2.4 band here is jammed bigtime that's why I use 5 Ghz for all my devices except my tablet and iphone.

 

[kpiontek]

I'll give one more chance

Thanks for the suggestions.

Soapy, I'll give Merlin's 3.0.0.4 270 26b a try, certainly can't hurt at this point.

jlake, I did remove all the wireless profiles already and entered them again and while it initially seems to connect at a higher rate it drops the rate quickly down, despite showing an excellent signal. InSSIDer3 reports -36dB on the 2.4GHz band with no overlap of other networks (that why I chose channel 1 which worked great on the WNDR3700).

Which raises the question by jim769 about interference, in inSSIDer I simply don't see any. The microwave is off, I made sure Bluetooth is off for the moment.

Leaves the possibility of a hardware problem for the 2.4GHz radio. The 5GHz radio is rock solid on both firmware I tried, Merlin's and the newest Asus where other people report a lot of problems with the 5GHz band. If all devices had the 5GHz radio too, I'd keep it but most don't.
Seems I might have to keep looking for another router and keep using the WNDR3700 until the dropouts become so frequent that I can't stand it anymore.

I'll let you know how it goes with Merlin's 3.0.0.4 270 26b unless somebody has some other ideas.

Thanks again.

Klaus

 

[SoCalReviews]

The RT-N66U with it's external antennas seems to be much more sensitive to picking up all broadcast signals and especially on the 2.4Ghz band. 5Ghz wireless radio transmissions have the advantage that they aren't used as often and they don't travel as far outside building structures. In recent years the 2.4Ghz band has become extremely crowded in most urban areas and this has caused Wifi reliability problems. I don't live in a particularly crowded neighborhood but I can detect up to twenty different 2.4Ghz broadcasts from inside my home at one time.

In my RT-N66U settings choosing the right channel(s) to use is absolutely critical to how well it works. Because of 2.4Ghz band crowding some channels are completely unreliable and some are rock solid in my area. I know this is a radio band channel crowding problem and not a RT-N66U router problem because at another location that has less 2.4Ghz crowding I have no problem with my exact same RT-N66U on those same channels I had problems with at my residence. This crowding issue also effected other major wireless router brands I used like Linksys and Netgear before I owned the Asus.

Try turning off the auto channel feature in the 2.4Ghz wireless settings and instead choose a fixed channel. Also try selecting the 20Mhz bandwidth instead of 20/40. If you live in the U.S. or have your channel options limited up to channel 11 my suggestion would be to try channels 1, 6 and 11 and then try 3 and 9 next. There are apps for smartphones like Wifi Analyzer and inSSIDer that can help you determine the best Wifi channels to use in your area.

 

[kpiontek]

I'm on channel 1

Hi SoCalReviews,

I'm in the US and yes, the 2.4GHz band is crowded here as well. That's why I chose channel 1 since it is not used by anybody here. I've attached an inSSIDer screenshot. The signal is around -35dBm with a link score of 100 reported by inSSIDer. All devices report excellent signal strength, yet the link speed is really low (5-25 Mbps), both reported by the devices as well as checked by downloads /speed tests etc..
The Netgear WNDR3700 never had that problem although it started to occasionally drop the wireless 2.4Ghz band recently and I had to restart the router. It was rock solid for more than 3 years, 24/7 otherwise. I think the radio might be going south which is the reason and I tried to replace it with the Asus thinking it would be as good or better.
I'll give the older Merlin firmware a shot but I'm leaning towards a defective 2.4Ghz radio in the router. I like the firmware and various settings but the low speed is unacceptable.
I probably just have to decide whether to replace it or simply return it. The router had just such high praise I thought it would be a great choice.

Thanks.

Klaus

 

[SoCalReviews]

You can't discount the possibility your RT-N66U has a bad 2.4Ghz radio or it could be a firmware problem. Try Merlin's firmware build(s). Maybe try an older Asus firmware. Try using some of the tips about flushing the router memory cache and re-doing the wireless radio settings. I am using the latest Asus .272/271 and it seems to be working well not just on one of my RT-N66Us (two in different locations as my residence and one at my business) but all three that I have owned for more than a year. From my experience over the last year this Asus is one of the most rock solid wireless routers I have used for the 2.4Ghz band.

The key is that wireless settings are set right and the fixed channel is not in conflict. At my residential location some of the channels that didn't work for me had great signal strength but for whatever reason they would drop connections. When I took that router to another location with the exact same settings it would have no problems at all. This wasn't the fault of the Asus. I would also have similar problems with my Netgear WNDR-3700v2 (which I still own) before I set it to the best working fixed channel. You need to go through trying all the 2.4Ghz channels (1 - 11) to see which ones work best in your location. If you really suspect the Asus router's 2.4Ghz radio is faulty then try using in in a different location with the same settings like I did before deciding to return it.

I am not telling you that you may or may not have a faulty radio in your router (or firmware issues) but what I always find strange is how so many people blame the wireless router radio and seldom look at the 2.4Ghz band interference and the quality of the devices they are connecting to. Those 2.4Ghz devices are just as important for sending and receiving the the wireless signal to and from the router. The 2.4Ghz radios in those devices or in devices that your neighbors are using can go bad and also cause signal connection problems for you. One more thing to note is whether you are using an XBox360. There were some known connection problems for it on the 2.4Ghz band that Asus released a settings change for with the more recent firmware.

 

[soapy]

ok 3 days later and my rt n66u is still behaving properly with merlins 270_26b software, what was happening was the 2.4 band was dropping its output to 72mbps according to insidder and when i connected a client it showed as connecting at 72mbps, now it is staying at 216mbps so it seems merlins software did the trick, i wont be updating the firmware unless it is definately fixed from all these bugs. i would like to thank merlin for all his hard work in producing his version of the FW for this router, it is much appreciated

 

[RMerlin]

ok 3 days later and my rt n66u is still behaving properly with merlins 270_26b software, what was happening was the 2.4 band was dropping its output to 72mbps according to insidder and when i connected a client it showed as connecting at 72mbps, now it is staying at 216mbps so it seems merlins software did the trick, i wont be updating the firmware unless it is definately fixed from all these bugs. i would like to thank merlin for all his hard work in producing his version of the FW for this router, it is much appreciated

3.0.0.4.372.31 also uses the same wireless driver as 270.26b, so it might be worth trying out, especially if you want to use AiCloud - there are major security holes in older FW versions in relation to AiCloud.

 

[kpiontek]

I give up

I tried Merlin's 270.26b with the same results.
5 GHz band is great, 2.4 GHz essentially is unusable.
I'm on channel 1 since that channel has no overlapping channels or networks, great signal strength reported (inSSIDer, INTEL PROset etc) but connection speeds are not great at all. Abysmal 5-12 Mbps, occasionally going as high as 36 Mbps). All 2.4Ghz devices are connected so slow, it's simply not working. And yes, I did clear the NVRAM, deleted the wireless profiles and created new ones but after briefly reporting good connection speed (like 144Mbps) they immediately drop to 5-12 Mbps and you barely can load websites. I played in addition with power settings (both down from 80 mW to 50 mW and up to 120 mW), no change. Disabled WMM APSD, no change. Disabled b/g protection, same thing. Set channel bandwidth to 20 MHz, no change. Set wireless mode to N only, no change. Control channel set to Auto, no change.

The WNDR3700 was in exactly the same spot, in the middle of the house, and it worked. Almost everything I read should have put the RT-N66U on at least the same level if not better but it isn't. So it goes back. Question is, should I give another Asus RT-N66U a chance, hoping the 2.4 GHz radio was simply defective?

What do you guys think, should I try a replacement RT-N66U? I like the firmware, in particular Merlin's (great work btw), but this unit is useless.

Thanks.

Klaus

 

[SoCalReviews]

"I did clear the NVRAM, deleted the wireless profiles and created new ones but after briefly reporting good connection speed (like 144Mbps) they immediately drop to 5-12 Mbps and you barely can load websites."

....144Mbps? This would mean that you are using 40 or 20/40Mhz bandwidth on the 2.4Ghz band...right? 40Mhz bandwidth on 2.4Ghz can become unreliable in moderately crowded areas which can result in lower throughput. Go back and look at the recommended settings changes I posted before....Set 2.4Ghz radio to 20Mhz only for 2.4Ghz band. You should see more consistent 2.4Ghz throughput of at least 20-30 Mbps and up to 60 Mbps depending on distance from router.

SNB article about 40mhz bandwidth mode in 2.4Ghz

http://www.smallnetbuilder.com/wireless/wireless-features/31743-bye-bye-40-mhz-mode-in-24-ghz-part-1


If you still have no luck trying everyone's suggestions here including Merlin's builds, settings changes, 20Mhz bandwidth, trying all eleven fixed channels, resetting and testing your various wireless devices etc..you could return your RT-N66U for a new router with the assumption it's 2.4Ghz wireless radio is defective. When you get the new replacement router test the 2.4Ghz wireless out of the box with it's default settings before you do any customizations or firmware updates and see if you experience similar issues. If you still have issues then try updating the firmware and settings changes such as fixed channel, etc..