Thanks for the redirect!
I was certain I had all recommended settings from the in the 99 posts I had read.
Switched to 20MHz and will now revert back some of the wifi settings and try beamforming disabled.
I'm rather new to this and hadn't read about beamforming. Disable that as well for both frequencies.
I'll update once we get back to that thing we call work.
You can leave explicit (802.11AC/AX) beamforming enabled as it actually can help (and typically doesn't hurt). The universal (legacy) is pretty bad on these routers though and causes people a lot of headache and should be disabled. If your router supports MU-MIMO you can toy with that too as it can have mixed results, if you have multiple bandwidth hungry devices it can give you a better total overall throughput, but if just one device downloading a large file it can potentially slow that one down a bit. Seems to vary with router, device, and situation.
Make sure airtime fairness is disabled on both bands, I think it is by default but check.
There is a debate over channels but in my area 2.4 is very congested, and while I don't use it much I do have a couple old devices that only support it, and I leave it on auto and that works best. It does typically pick a non-1/6/11 channel but that is often necessary these days unless you're in an isolated area.
5Ghz as long as you don't let it use DFS frequencies will usually pick one that is fine.
160Mhz is often unnecessary and problematic (since it will overlap DFS), 80 is a good setting (or 20/40/80 with 160 disabled as it sounds like you have it now). On 80Mhz with AC clients you should be able to get 400-500 or more (assuming dual stream devices connecting at 866.6 mbit which are the most common) and AX clients can double that, which should be plenty.
Personally I like to set it to N only on 2.4 and N/AC only on 5, disabling A/B/G, but probably not a big difference there. I don't know what selections the AX routers have but I think it would be N/AX on 2.4 and N/AC/AX on 5.
QOS can cause problems, what is your internet speed? If it is decent (hundreds of megs) it likely isn't necessary. Maybe only on the upload side if you have a slow upload speed and people are saturating it (you'd be surprised though, even video calls don't take that much).
Personally I use the same SSID for both 2.4 and 5 and don't have problems but I also don't have a lot of IOT devices or others that tend to hop around. Stuff I have all prefers 5Ghz and I have roaming aggressiveness set to high where possible so it won't "stick" on 2.4 when I come back from outside etc.
If you want the best of both worlds, you can set up one network with the same name (YourNet) then another with 2 different names (YourNet-2.4 and YourNet-5). One can be your main LAN (typically the one with the same name for both bands) and the one with two names can be your Guest Wireless. Note the behavior of GW1 is different than 2 and 3 - if you have LAN access disabled it uses different subnets and VLANs to isolate stuff. If you have LAN access enabled it functions pretty much as just another SSID on your main LAN without any isolation. For GW2 and 3, regardless of whether "Access LAN is enabled" it is an extension of your main LAN and uses firewall rules to prevent communication. For simplicity, you may want to just stick with 2 and 3 leaving 1 disabled. You can choose whether to enable "access LAN" or not for each guest network. Now you can assign phones and laptops and stuff that moves around to the main LAN, and IOT/stuff that doesn't move to the band you want it to stick on.
Couple caveats/notes
If you use GW1 and enable isolation - main LAN can access Guest devices, but guest devices cannot access main LAN. This is good if you want to stream from your phone on main LAN to TV on guest, etc.
GW2 and 3 totally isolated, main LAN cannot reach them and vice-versa if LAN access is disabled.
When lan access is disabled, devices on the guest network also can't access each other.
My setup is main lan - same name, laptops and phones use this
GW1 - Guest network - also same name for both, I also have some physical ports mapped into this - used for guests, neighbors, and when I repair a PC (wired or wireless) for someone that I don't trust to put on my main LAN. LAN access disabled.
GW2 - IOT network or "semi-trusted" network - also same name for both but if I had a lot of this sort of thing I might split it up. I disable access LAN here too. If I wanted to stream from my laptop to my TV I'd have to jump on the IOT network with the laptop or enable LAN access, but I have a desktop hardwired to TV via HDMI so never do that.
