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RT-AC66R Random Wireless Slow Speeds

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pioneer_sti

New Around Here
UPDATE: After playing with settings found a way to get it working, but not ideal. More info 3 post down

Hi,

Hopefully someone here can help with this issue. In a nut shell, cable connected (LAN) devices are always at full speed but wireless will just drop way down in speed requiring a reboot. Wireless speed could stay high for 1 hour or 2 days, but will drop within 48 hours.

For reference I have tried 'out of the box' firmware, latest stock ASUS firmware and latest Merlin. Also after reading my second email, please note the old RT-N16 is still providing normal wireless 5 days later.

Sorry for the long first post, but I figure all the facts would be helpful. At this stage, I'm thinking it's time to throw this router in the garbage, unless one of the great minds here can solve the mystery.

Below is the first email I sent to ASUS:

Problem: Wifi slows down randomly. It will be at full 50 Mbps, and then in usually a day or 2 (sometimes less) will drop to between 0.5 to 3 Mbps. While this is happening, anything connected via cable to the LAN outputs has full speed of 50 Mbps, eliminating ISP bandwidth issues as a problem. I have an RT-N10P (serial ********) that I have since placed right next to the RT-AC66R, and even when RT-AC66R has slow wifi the RT-N10P (connected via LAN to RT-AC66R) has fast wifi, so location or interference is not an issue. A reboot (or occasionally 2 or 3) is required to get back the correct speed wifi.

I also have an ASUS RT-N16 (serial ********), and neither that nor the RT-N10P when it was running stock Asus firmware and now Tomato by Shibby have ever had any wifi issues.

This seems to be an old problem as can be seen from this thread on http://forums.smallnetbuilder.com/showthread.php?t=9765

The RT-AC66R has been upgraded to firmware 3.0.0.4.376_2524.

Looking forward to suggestions to fix this issue, and no longer have to doing twice daily speed tests and almost once daily reboots.

For reference, I did try setting the router to a single channel (Channel 1, as it was always free with inSSIDer checks), but the problem still occurs.


Their reply:

I remember that the bandwidth tends to vary in speed for various reasons, the main one is the number of connected to your modem speed that makes you 54Mbps devices is the most you can get to have, but if you have a width of less than performing a test strip so you mark your connection only.

I'll share the link to downloading the manual from your device and verify your information.
http://www.asus.com/Networking/RTAC66R/HelpDesk_Manual/


My Reply Back (3 days ago no reply yet.. :rolleyes: ):

Unfortunately I doubt this has anything to do with connections. When the speed tests are performed the ONLY devices on the router (and modem) are the PC doing the test connected to LAN 1 and the cell phone doing the wireless test, and neither is downloading any data, nor are they doing the speed tests at the same time. There is NOTHING else using any bandwidth, or even connected.

As I have two ISPs (using two different modems) in two different rooms I chose to conduct a test over the last 48 hours. To make the below easier to understand we will call one pair Room 1 and ISP 1 and the other pair Room 2 and ISP 2.

Initially the RT-AC66R was connected to ISP 1 in Room 1, and as mentioned would randomly suffer from slow wireless speeds (0.5 to 3.0 Mbps) while the LAN connections still showed full speed of (50 Mbps). The wireless would remain low until a reboot was performed, after which wireless speed would immediately be back up to the full 50 Mbps.

For well over a year I have had the RT-N16 connected to ISP 2 in Room 2 and that router has never suffered a drop in speed over the wireless connections. That connection is a max of 8 Mbps, and wireless tests always show speeds of around 8 Mbps.

Over 48 hours ago I switched the two routers around, so that the RT-AC66R is now on ISP 2 in Room 2, and the RT-N16 is now on ISP 1 in Room 1. The RT-N16, 48 hours later is still showing full 50 Mbps over the wireless connection. The new RT-AC66R, which has been moved to Room 2, has suffered twice in 48 hours from a loss of wireless speed, and required rebooting to gain back full wireless speed (speeds dropped to between 0.2 to 1.2 Mbps). So twice in 48 hours the RT-AC66R loss wireless speed on a connection and in a room that the RT-N16 has run for a year without a single issue. Add to that the RT-N16 is working perfectly for over 48 hours on the ISP, and in the room, that the RT-AC66R could not go more than 48 hours without losing wireless speed.

Both the RT-AC66R and the RT-N16 are running the Asus default settings. The only thing changed in the setup is the login and the network key. All other settings are default. The only setting I ever changed on the RT-AC66R was to change to channel 1 to see if that solved the problem.

Now let's add one more fact. The little RT-N10P was initially providing the wireless connected to ISP 1 in Room 1, but it's signal strength wasn't quite enough, which was the reason for buying the RT-AC66R. So for 4 weeks the RT-N10P in Room 1 was working perfect with no loss in wireless speed, yet the RT-AC66R couldn't work for more than 48 hours without losing wireless speed.

That means two Asus routers can work perfectly in a location that the RT-AC66R can't work perfectly.

One other thing worth mentioning is that the RT-AC66R tends to get quite hot, whereas both the RT-N16 and the RT-N10P are usually just a bit warm. Room temperature is usually 26ºC (79ºF).

With all due respect, when you reply please do not waste my time with a link to the manual. I have taken the trouble to do extensive testing to describe the issue and help you evaluate the situation, therefore please do one of the three in your next reply, so we don't have to trade 20 emails back and forth with the same end result.

1. Provide me with a possible solution to the specific issue to correct the router's failure to maintain a proper wireless speed.
2. I bought the router in Canada (Best Buy) but I live in Barbados, so provide me with information on how and where to send the router in for inspection, repair or replacement.
3. Advise me as a loyal Asus customer that you can help me no further, and I will 'bin' this router and purchase a different one.
 
Last edited:
Yikes. Quite a read. You need to do some more in-depth trouble-shooting so that you can more accurately pin-point where the problem(s) are coming from.

Are you running any 802.11b or 802.11g clients?
Are you running the wireless routers in n-only, auto, or legacy mode?
Are both routers running in 2.4Ghz? If so, I don't think they should be close to each other.
You should read some wifi and network/LAN FAQs to make sure you are avoiding common mistakes.

Make sure you read the following;
http://forums.smallnetbuilder.com/showthread.php?t=2506
http://forums.smallnetbuilder.com/showthread.php?t=12825


On a personal note, please remember that your emails to Asus (or any customer service) are being read by a person like you and me, not some faceless corporate robot. The expression "you will catch more flies with honey than vinegar" comes to mind.

Good luck. :)
 
Last edited:
Yikes. Quite a read. You need to do some more in-depth trouble-shooting so that you can more accurately pin-point where the problem(s) are coming from.

Are you running any 802.11b or 802.11g clients?
Clients vary. I've had the issue with Nexus 4, Surface pro, Dell D630 laptop or IBM T42p connected. I don't think it's isolated to one type of client as the listed equipment varies from very current to several years old. I'll see if I can get details on all four of the clients.
Are you running the wireless routers in n-only, auto, or legacy mode?
I'll check on that get back to you. Whatever it is, it is the default setting from Asus.
Are both routers running in 2.4Ghz? If so, I don't think they should be close to each other.
Right now the RT-N16 and the RT-N10P are right next to each other, very close, but they have been trouble free for almost a week, and are always playing nice, which I didn't expect. I initially setup the RT-AC66R alone to test it for a week, but after all the constant wireless loss of speed, I then setup the RT-N10P (using an openVPN) right next to the RT-AC66R. The RT-AC66R feeds the RT-N10P via LAN, and even when the RT-AC66R would drop wireless strength, the RT-N10P would still be delivering full wireless speed.
You should read some wifi and network/LAN FAQs to make sure you are avoiding common mistakes.

Make sure you read the following;
http://forums.smallnetbuilder.com/showthread.php?t=2506
http://forums.smallnetbuilder.com/showthread.php?t=12825

I read the above and there are certainly some things I can and will try, but I have covered most of it already.

On a personal note, please remember that your emails to Asus (or any customer service) are being read by a person like you and me, not some faceless corporate robot. The expression "you will catch more flies with honey than vinegar" comes to mind.

I appreciate what you are saying, and I am usually very polite, but his reply to read the manual and the statement (which wasn't very coherent) about connected devices served no purpose at all. It seemed like a generic 'can't be bothered' response which I see all too often these days. Hearing about a drop from a 50 Mbps to 0.5 to 3.0 Mbps, he didn't opt to ask what devices where connected to elicit a reply from me and start a dialog toward diagnosing the issue.

Good luck. :)

Thanks for your response and taking the time to read my post.... well more like my book .... :D I'll follow up on your suggestions and do a little more research but I still think this is a hardware issue. I'll report back if anything works. I am in no way an expert when it comes to routers, but I started life repairing VHS machines, and have been involved with electronic components most of my life, right up to now installing and tuning engine control units for motorsport vehicles, and in almost all cases harsh intermittent faults are almost always caused by faulty hardware not software. I'll gladly be wrong in this case about a hardware issue as this router wasn't cheap, but it has certainly been very disappointing so far.
 
First thanks to Nullity who got me started on something to check and try. Unlike ASUS support which was basically useless he offered some input and something to look into.

From everything thing I have read on this forum, the ASUS AC routers seem to either have immature firmware issues, or hardware issues. Too many varying issues to be simple setup problems and couple that with different solutions required for the same issues, and you have the recipe for 'slot machine' products, pull the handle and see if your product is a winner (i.e. that it actually works the way it should).

For my issue, the magic combination was the below settings. Change any and the router goes back to randomly losing wireless speed. How I envy the guy with the same problem who just had to select a single channel on the 2.4 GHz to cure the same problem.

Give the 2.4 GHz and the 5.0 GHz different SSID names.
Run the 2.4 GHz in Legacy
Run the 5.0 GHz in Legacy
Change the 5.0 GHz to channel 36

If any of the above are changed the router will loss wireless speed. Again, this is my solution, but from what I've read here the solutions vary or are simply never found or reported back in the thread.

One thing is for sure, this will be my last ASUS product. It is a shame to spend money on a product only to find you have to spend a lot of time to get it to run it in a mode comparable to cheaper products, and the extent of tech support is a message telling you to read the manual.
 

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