My model isn't listed anywhere that I've seen, but I think the RAX40 is the closest. Mine is the RAX45 6-stream wifi router. I first posted on the general Nighthawk wifi routers group. Thanks @michaelkenward for your advice to post here instead and for your clarifying questions.
I got this router in February and immediately had issues with very slow speeds on the 2.4Ghz band only. The problem was solved during my free-tech support period by changing to older firmware (V1.0.2.64_2.0.41). Last week, the slow speeds and buffering returned. I asumed there had been a firmware update and that's what cause the return of super-slow speeds.
I changed back to firmware V1.0.2.64_2.0.41, which had previously solved the problem (I also turned off auto-updates). This time the solution did not work. My download speed is often under 10Mbps, again (last check it was 9.54). I have no idea what to do now. Please help!
Modem: Hitron EN2251 -- it is not also a router. It has one ethernet port and a couple of voice inputs.
For the 2.4GHz band, manually select a channel instead of using the "Auto" setting, while auto works well in most cases, in heavily congested environments, it can cause issues by simply not finding any good channels and thus constantly scanning and switching channels depending on which has lower airtime use at the given moment which will change often based on other people in the area.
Also consider experimenting with the 20/40 coexistance setting. sometimes even in congested situations, it can provide a good speed boost, especiallly if neighboring APs are fairly close to the noise floor.
Beyond that, when it is performing slow, check other WiFi drvices on the same band to see if they are having similar slowdowns.
If it is just a single device, then I recommend also using the debug page on the router at routerIP/debug.htm and start logging, and during that process have the device in question disconnect and reconnect a few times. Then check for entries listing the device's MCS rates. Some WiFi adapters will behave strangely or simply not report all supported rates, or engage in other behavior that causes a very low PHY rate to be used, in some cases, it could simply be a driver issue with the WiFi adapter. I have seen this happen a few time with some of the more obscure WiFi chipsets.
For the 2.4GHz band, manually select a channel instead of using the "Auto" setting, while auto works well in most cases, in heavily congested environments, it can cause issues by simply not finding any good channels and thus constantly scanning and switching channels depending on which has lower airtime use at the given moment which will change often based on other people in the area.
I was on channel 9 before, but it seems that was reset to auto with the firmware update (maybe?). I have switched it to 11.
Also consider experimenting with the 20/40 coexistance setting. sometimes even in congested situations, it can provide a good speed boost, especiallly if neighboring APs are fairly close to the noise floor.
Okay -- what is that, where do I find it, and what do I need to do? (Sorry, not that knowledgable)
Beyond that, when it is performing slow, check other WiFi drvices on the same band to see if they are having similar slowdowns.
If it is just a single device, then I recommend also using the debug page on the router at routerIP/debug.htm and start logging, and during that process have the device in question disconnect and reconnect a few times. Then check for entries listing the device's MCS rates. Some WiFi adapters will behave strangely or simply not report all supported rates, or engage in other behavior that causes a very low PHY rate to be used, in some cases, it could simply be a driver issue with the WiFi adapter. I have seen this happen a few time with some of the more obscure WiFi chipsets.
Everything slows down at once, across all decvices. Thanks for being so thorough!
For the 20/40 MHz coexistence, it is a setting in the WiFi settings menu. It will be titled "Enable 20/40 MHz Coexistence" and will be enabled by default. That setting will cause the router to use 20MHz channel width instead of 40MHz channel width, thus half the throughput if it detects any overlapping APs. In a truly congested environment, 40MHz can slow you down, as additional airtime sharing will take place, but if the neighboring APs are far away, then that airtime sharing issue may not happen and you will get a nice performance bump.
Beyond that, try specifying a channel manually.
Also if unchecking the 20/40 MHz coexistence does not fix the issues, then check it again, as it is a useful feature in the vast majority of cases.
I did a factory reset last night, and tested speeds with the new firmware and the old, with and without disabling the 20/40 MHz coexistence setting, and on a specific channel, not the auto setting. My download speeds on 2.4 are still under 10Mbps, sometimes as low as 1.5. Intestingly, the upload speeds were sometimes respectable (7-11) at the same time. 5g download speeds are 100 or higher.
Those results are very strange, almost as if something is causing it to use a very low PHY rate. Given those results, if I were personally experiencing them, my next stap in tracking the issue down, would be to use the debug function in the router at routerIP/debug.htm and starting a debug log capture, then while capturing it, doing multiple download benchmarks in a row, then saving the debug log.
Then looking through the log files for Wifi related ones, different models wil have different names, but there will often be something like wltest or some other similar name that should have WiFi client info. They are typically in either the main part of the zip file or in a tmp folder)
At that point you can skim through it looking for error messages, as well as detailed connection stats for the device having the throughput issue (you will have to search for it via its MAC address).
Sadly the debug data are not suitable for posting on a public forum, as they will also contain every changed setting, thus containing WiFi passwords, dyndns info, and anything else changed.
While much of the log info will be unrelated to the issue, they are pretty well laid out and are useful in tracking down weird issues like this.
If you are able to look at the data, check for things such as a very high noise floor on the 2.4GHz band, as well as low connection rates while a client is close to the router and actively downloading.
If you notice a high noise floor and are not in a heavily congested environment, then make sure no unshielded USB 3.0 devices are connected and close to the antennas.(ideally the noise floor should be in the -90dB range.
