Database Users

Wifi 802.11n 5Ghz working for anyone?

I found the option in the settings where the band can be forced to 2.4, 5 or Auto. On either Auto or 5 the N4 doesn't "see" my 802.11n router (other clients are connected to it just fine). Only b/n/g seems to work for me. The router is a Linksys E3000 running DD-WRT if that matters.
Anyone else?

Well, the Nexus 4 doesn't support 802.11a (see wikipedia etc.)
But 802.11n at 5 Ghz should work.

infoflo said:
Well, the Nexus 4 doesn't support 802.11a (see wikipedia etc.)
But 802.11n at 5 Ghz should work.
Click to expand...
Click to collapse
Actually, it does.
Wireless RF Module - Atheros WCN3660
Quote:
Manufacturer: Qualcomm
Bluetooth: BT 3.0/4.0 Low Energy
Wi-Fi: 802.11 a/b/g/n (2.4/5 GHz)
FM: Hardware supported

I don't have wireless A, but one thing to try. Is your 5ghz and 2.4ghz broadcasts named the same? For instance on my wireless N setup I have the router broadcast ROUTER5 and ROUTER2.4 so I can specify which band to connect to. This has eliminated a lot of trouble of my wireless devices not choosing 5ghz when I want them to. So my Nexus4 just connects to ROUTER 5 and I know it is 5ghz.
jasonwc said:
Actually, it does.
Wireless RF Module - Atheros WCN3660
Quote:
Manufacturer: Qualcomm
Bluetooth: BT 3.0/4.0 Low Energy
Wi-Fi: 802.11 a/b/g/n (2.4/5 GHz)
FM: Hardware supported
Click to expand...
Click to collapse

The SSIDs are different for "5" and "2.4" for exactly the reason you mentioned. But no matter what I can't see the "5" SSID from the N4, while either wifi clients can see both at the same time. The router support simultaneous 2.4 and 5.

Yes. 5Ghz works.
I use it in my house. I'm on it right now with my N4.
Check the security on your router.
You should have a WPA2/PSK AES encryption or leave your network open.
You'll also want to verify your router is broadcasting.
Since your router was flashed with DD-WRT, verify you are in mixed mode or some sort of N G combo.

Thanks for confirmation. It's strange that the phone doesn't even see the router at all, I tried various mixed modes, channels, SSID broadcast is enabled, etc. Other clients have no problems with the router.

I haven't tried this yet, but from reading other reports it may be the case that the N4 (and the N10) only support the 5Ghz band with 20Mhz channels, not 40Mhz. My router is configured to use 40Mhz only so that might explain why the N4 cannot "see" it.
http://www.dd-wrt.com/wiki/index.php/Wireless-N_Configuration#20MHz_vs_40MHz

running my Nexus 4 on 5GHz N mode on a Linksys EA6500. My channel width is set to auto so maybe that is why it can be seen and used.
General question though, why have you chosen to use 802.11a anyway? What benefits are there? (honestly curious)

Sort of off topic, but who the crud uses 802.11a?
Sent from my Nexus 4 using xda app-developers app

DarkRyoushii said:
General question though, why have you chosen to use 802.11a anyway? What benefits are there? (honestly curious)
Click to expand...
Click to collapse
The subject of my topic is wrong. It should have said 802.11n on the 5Ghz band, not 802.11a. I edited the subject now.
I prefer 5Ghz when possible because I seem to be the only AP on that band whereas 2.4Ghz is crowded.

sirxdroid said:
I found the option in the settings where the band can be forced to 2.4, 5 or Auto. On either Auto or 5 the N4 doesn't "see" my 802.11n router (other clients are connected to it just fine). Only b/n/g seems to work for me. The router is a Linksys E3000 running DD-WRT if that matters.
Anyone else?
Click to expand...
Click to collapse
I have the same router with DDWRT also and my N4 cannot see my n router either. I will look into the band settings tonight.

Just chiming in, Linksys E3000, DDWRT and my 5Ghz network works like a charm

5Ghz works for me just fine.

still having wifi issues, wddrt flashed firmware(iv'e tried all settings) wasted 24hours i think trying to figure it out, solid connection but wifi seems broken, can't download stuff but can browse google playstore
my other wifi devices have NO ISSUES at all with this router
cannot run speedtest, can only run ONE certain type of texting app(strange) others won't connect online
its like my n4 has a 'firewall' or something
seems my best option is to pick BG-MIXED mode! alot mor apps connecting to the internet now but not all! at least im getting progress

sirxdroid said:
I found the option in the settings where the band can be forced to 2.4, 5 or Auto. On either Auto or 5 the N4 doesn't "see" my 802.11n router (other clients are connected to it just fine). Only b/n/g seems to work for me. The router is a Linksys E3000 running DD-WRT if that matters.
Anyone else?
Click to expand...
Click to collapse
Change your channel to 40 or 48. Mine didn't work before but after changing my AP channel to 48, my N4 can see the 5GHz AP now.

junks2010 said:
Change your channel to 40 or 48. Mine didn't work before but after changing my AP channel to 48, my N4 can see the 5GHz AP now.
Click to expand...
Click to collapse
Changing my AP's channel to 48 from 40 seemed to work for me. My Nexus 4 can now see my 5GHz AP.
Thanks!

lamb_1234 said:
Changing my AP's channel to 48 from 40 seemed to work for me. My Nexus 4 can now see my 5GHz AP.
Thanks!
Click to expand...
Click to collapse
Thanks alot ! I had this exact problem with my Tomato-flashed Linksys E3000. I changed the channel of 5ghz from Auto to 48 and voila, Nexus 4 is now cruising happily.
Before, my Nexus 4 did not even detect my wifi N 5ghz AP while all my other devices could. The strange thing is my Nexus could see my neighbors' 5ghz APs but just not mine.

utes said:
Thanks alot ! I had this exact problem with my Tomato-flashed Linksys E3000. I changed the channel of 5ghz from Auto to 48 and voila, Nexus 4 is now cruising happily.
Before, my Nexus 4 did not even detect my wifi N 5ghz AP while all my other devices could. The strange thing is my Nexus could see my neighbors' 5ghz APs but just not mine.
Click to expand...
Click to collapse
What Channel Width do you use? Auto/10/20/40 - at least these are the options in DD-WRT?
I still can't get my N4 to see my DD-WRT router's 5Ghz AP no matter what I try. I have since acquired an HTC One X+ phone and that has no problem seeing it, together with a bunch of other devices in the house, including a Chromebook. Something going on with the wifi chip and/or software in this LG N4.

Try 20mhz and a low channel like 40 or 48. Works perfect for me on dd-wrt
Sent from my Nexus 4 using xda app-developers app

wifi issues on N4 possible fix?

for those with wifi 'broken' try to change your router settings to WPA2 personal (TKIP+AES) that seems to work for me now,
other settings 'broke' the wifi
this might be just an issue with must me and my router
*spoke too soon: still broken, it only works certain times, mostly it just spins when i try to connecto to online
the wifi icon keeps flashing a black dot... that means the wifi is NOT working right? it should be just a solid blue bars?
on wifi advanced settings, WPS Pin Entry - what is this and do i need to enter that pin on my router?

still no luck with wifi on my network after flashing back to stock 4.2 from 4.2.1
same 'broken' wifi
might be this phone's wifi hardware is incompatible with wDDRT router?
Firmware: DD-WRT v24-sp2 (10/10/09) std
my other wifi devices work perfectly fine, so im really stumped
in phones advance wifi settings it has this WPS entry - what is this and is it somehow not allowing me full wifi?
i can view playstore,, it checks and loads my gMail but it won't connect to websites
it takes so long to download and install apps from playstore, i have to hit cancel, redownload, reinstall to get it working,etc. its not 'instant' like normal 20Mbps wifi should be
ran speedtest.net app and it wont connect to any servers
if anyone has clues to why my wifi is broken, please PM me thanks
it get a blue 3 to 4 bars on wifi signal but it keeps having this 'black' dot flashing in that wifi signal bar, (what is that?)
shows connected to my wifi at 72Mbps at good strength

I found my solution: in my router I unchecked the option WMM (Wi-Fi-multimedia)-settings (2.4GHz b/g/n). After I activated it, my data speeds increased enormously. Try it & report!

danielvc said:
I found my solution: in my router I unchecked the option WMM (Wi-Fi-multimedia)-settings (2.4GHz b/g/n). After I activated it, my data speeds increased enormously. Try it & report!
Click to expand...
Click to collapse
thanks i will look for that option in my router but don't think i have it

Public wifi and my work wifi working perfect with n4. So it definitely my routers wddrt firmware issues with n4... still gottta figure it
Sent from my TC970 (Wi-Fi) using xda app-developers app

My n4 will not connect to any of the WPA2 AP's around here.

I have the opposite problem. I can connect to my WPA2 router at home just fine but cannot connect to the WEP wifi at work. Well, not reliably. I've gotten connected twice, but was unable to recreate the conditions.
-Matt

I had speed problems with my 5GHz band at home. Connected, but couldn't get over 1Mbps on my 30+ connection. Connected to the 2.4Ghz band and I get significantly faster speeds. Haven't had problems connecting though.

siscim23 said:
I had speed problems with my 5GHz band at home. Connected, but couldn't get over 1Mbps on my 30+ connection. Connected to the 2.4Ghz band and I get significantly faster speeds. Haven't had problems connecting though.
Click to expand...
Click to collapse
I've noticed similar behavior, seems like my 5ghz signal strength is much weaker than my 2.4ghz signal according to my n4.

So this n4 is picky about. Certain WiFi networks.configs
Sent from my Nexus 4 using xda premium

Sometimes, my N4 loses wifi connection at work. It's inconsistent. My work wifi is open but MAC filtered.
There have been 3-4 times when I noticed that it lost wifi connection. I had to turn off wifi radio and back on to reconnect.
OTOH, connection to home DD-WRT wifi router is rock solid.

Set lease time for as long as possible, it normally this is 2 weeks..
sent via xda premium with Nexus 7 or Nexus 4!

I flashed my stock recovery backup and my wifi is working again!

jim.k.yee said:
I flashed my stock recovery backup and my wifi is working again!
Click to expand...
Click to collapse
??????
very strange !!!!
can you test to flash back CWM recovery and test again the wifi ?

Hello, I am also having problems with WIFI. I've tried a lot of things (change the router configuration, the cellular exchange kernel, etc ...) but I could not fix this problem. Can you give any more ideas? I've even thought about buying another router but can be giving the same problem.
I used my wife's phone as a router and it works normally, but when I connect directly to the router from home and he trasfere data only for a few moments and then transferring data, although still seem the symbol of wifi connected.

I found changing a setting on the Nexus 4 seems to have remedied most of my WiFi issues. Forcing the WiFi frequency band to 2.4GHz only instead of Auto appears to have done the trick for me.
In WiFi if you select Settings and Advanced under Wi-Fi frequency band there is an option to force 5GHz or 2.4GHz with the default on Auto.

BigVDawgy said:
I found changing a setting on the Nexus 4 seems to have remedied most of my WiFi issues. Forcing the WiFi frequency band to 2.4GHz only instead of Auto appears to have done the trick for me.
In WiFi if you select Settings and Advanced under Wi-Fi frequency band there is an option to force 5GHz or 2.4GHz with the default on Auto.
Click to expand...
Click to collapse
Will try it, thanks.

BigVDawgy said:
I found changing a setting on the Nexus 4 seems to have remedied most of my WiFi issues. Forcing the WiFi frequency band to 2.4GHz only instead of Auto appears to have done the trick for me.
In WiFi if you select Settings and Advanced under Wi-Fi frequency band there is an option to force 5GHz or 2.4GHz with the default on Auto.
Click to expand...
Click to collapse
I tried but did not fix, thanks for trying to help.

Lucena04 said:
I tried but did not fix, thanks for trying to help.
Click to expand...
Click to collapse
for me too
anyways thanks for the help...

N4 5ghz connection

I bought a new router a few weeks back for the express purpose of using 5ghz. I set it up and I remember it working at the time, but stopped soon after and I never looked back into it until now,just used the 2.4.
I can see the network, and a few other 5ghz networks in the area, but when I try to connect the signal strength drops and disappears for a few seconds. Looking at 20 ft line of sight.
I've set the router to 20mhz band, used every available channel, and disabled encryption. Nothing so far. Any suggestions?
Buffalo WZR-1166DHP 2.13
AOKP build 1-24
.98 modern

Not that this helps but my wifes N4 cannot connect to any 5GHz network either, i have tried changing the channels etc. but to no avail.
It used to work brilliantly with 4.2 so the blame lies with Google in the latest updates.

I've searched for your problem and I've found that some channels were missing and google added them in 4.4 update ...what android are you on ?

Stock 4.4.2, nothing i have found works thats for sure.

I am having a similar issue, 2.4ghz signal is full strength but 5ghz struggles to keep one bar whereas my Nexus 7 is full strength on both.
Router is an Asus RT-N66U and I'm running CM11 Snapshot M2 on both devices.

Wifi problem - what router do you use and what is the configuration?

Some people have no problem, while others like myself have issue. So let's figure out if this is a router config issue, since most Wifi problem with Android have to do with the router itself. I'll start off with mine.
Tablet date of purchase: September 12th
Router: ASUS RT-N66U dual-band (2.4 & 5 Ghz) with latest firmware
Wireless configuration:
- 2.4 Ghz for B/G
- 5 Ghz for N only
Distance from router to tablet: less than 50 ft
Issue: sporadic network connection. I got full Wi-fi signal bars, good Internet connection, but then cut-out and no connection. Back again after 10-20 seconds.
Fix(?): Changed the router configuration for the 5Ghz radio from 20/40 Mhz to 40 Mhz. This seems to tame the problem. I still have sporadic connection, but far less and connection is back again after a few seconds.

lanwarrior said:
Some people have no problem, while others like myself have issue. So let's figure out if this is a router config issue, since most Wifi problem with Android have to do with the router itself. I'll start off with mine.
Tablet date of purchase: September 12th
Router: ASUS RT-N66U dual-band (2.4 & 5 Ghz) with latest firmware
Wireless configuration:
- 2.4 Ghz for B/G
- 5 Ghz for N only
Distance from router to tablet: less than 50 ft
Issue: sporadic network connection. I got full Wi-fi signal bars, good Internet connection, but then cut-out and no connection. Back again after 10-20 seconds.
Fix(?): Changed the router configuration for the 5Ghz radio from 20/40 Mhz to 40 Mhz. This seems to tame the problem. I still have sporadic connection, but far less and connection is back again after a few seconds.
Click to expand...
Click to collapse
I have a TP link single band N router configured for b/g/n. Both my shield portable and shield tablet have issues with wifi. My nexus 7 and my moto g are perfectly fine on it.
I think in my case I've narrowed it down to the router, though. I have a second router upstairs, also tp link single band N (different model). It is configured in bridge mode for the main router. Both shield devices are perfectly fine when connected to it. Unfortunately it only serves a small portion of my house and is much slower over all.

A robust wifi area will hide most any weak wifi. Catch is most areas are not robust.

rushless said:
A robust wifi area will hide most any weak wifi. Catch is most areas are not robust.
Click to expand...
Click to collapse
What do you mean by robust? Not crowded?

Strong signal with minimal set up conflicts.

lanwarrior said:
Some people have no problem, while others like myself have issue. So let's figure out if this is a router config issue, since most Wifi problem with Android have to do with the router itself. I'll start off with mine.
Tablet date of purchase: September 12th
Router: ASUS RT-N66U dual-band (2.4 & 5 Ghz) with latest firmware
Wireless configuration:
- 2.4 Ghz for B/G
- 5 Ghz for N only
Distance from router to tablet: less than 50 ft
Issue: sporadic network connection. I got full Wi-fi signal bars, good Internet connection, but then cut-out and no connection. Back again after 10-20 seconds.
Fix(?): Changed the router configuration for the 5Ghz radio from 20/40 Mhz to 40 Mhz. This seems to tame the problem. I still have sporadic connection, but far less and connection is back again after a few seconds.
Click to expand...
Click to collapse
I'm using a similar setup, but an ASUS RT-AC66U instead of the N66. A frequencies are mixed-mode, and my 5GHz is 20/40Mhz. I can pull a consistent 20 Mbps down usually, without any issues. 50 Mbps down if I'm the only active network user at the time.
Wifi signal is usually at 2 bars, but I'm getting the same signal level out of the Shield Portable, my Nexus 5, and Nexus 7 on my 5Ghz net. My 2.4Ghz net is usually always full strength.

Kirotan said:
I'm using a similar setup, but an ASUS RT-AC66U instead of the N66. A frequencies are mixed-mode, and my 5GHz is 20/40Mhz. I can pull a consistent 20 Mbps down usually, without any issues. 50 Mbps down if I'm the only active network user at the time.
Wifi signal is usually at 2 bars, but I'm getting the same signal level out of the Shield Portable, my Nexus 5, and Nexus 7 on my 5Ghz net. My 2.4Ghz net is usually always full strength.
Click to expand...
Click to collapse
That's interesting. I wonder if my N66U is unable to maintain a stable and consistent 5Ghz connection. So you have no problem with the connection like mien?
Do you use DD-WRT or stock ASUS firmware (what version?). I may end up buying the AC66U just to test it out.

Using a virgin hub which is a netgear i belive, 2.4 is solid even two stories away from the router. 5g is still there 2 stories up but will drop out, only 1 story up it's 1-2 bars but never drops out. 5g band on router set to 38-40ish range.
Sent from my SM-N9005 using Tapatalk

funb0b said:
Using a virgin hub which is a netgear i belive, 2.4 is solid even two stories away from the router. 5g is still there 2 stories up but will drop out, only 1 story up it's 1-2 bars but never drops out. 5g band on router set to 38-40ish range.
Sent from my SM-N9005 using Tapatalk
Click to expand...
Click to collapse
Don't you need 5Ghz to play GRID? If I use 2.4Ghz, GRID will "complain" and won't start any game I selected.

lanwarrior said:
That's interesting. I wonder if my N66U is unable to maintain a stable and consistent 5Ghz connection. So you have no problem with the connection like mien?
Do you use DD-WRT or stock ASUS firmware (what version?). I may end up buying the AC66U just to test it out.
Click to expand...
Click to collapse
I have the AC66U as well and have no problems at home but have severe wifi difficulties at work or when hotspotting to my mifi which is annoying.

lanwarrior said:
Don't you need 5Ghz to play GRID? If I use 2.4Ghz, GRID will "complain" and won't start any game I selected.
Click to expand...
Click to collapse
I get full bars in the lounge which is where I would do any grid [emoji4]

lanwarrior said:
That's interesting. I wonder if my N66U is unable to maintain a stable and consistent 5Ghz connection. So you have no problem with the connection like mien?
Do you use DD-WRT or stock ASUS firmware (what version?). I may end up buying the AC66U just to test it out.
Click to expand...
Click to collapse
Stock. Whatever the latest version of firmware is too- I update when it's available.

When I had problems with my Luxor tv connecting changing channel on router from auto to one of the numbered ones fixed it, perhaps it has the bug where your device ends up getting the same IP as the router. Worth a go!

Latest update breaks 5 ghz wifi

So I finally figured this out - pre the latest update 5 ghz wifi on the Oneplus 6t worked flawlessly. Then the latest update came down (ironically over 5 ghx wifi) applied and rebooted and poof 5 ghz wifi no longer works. It connects, it gets ip, it can see the router everything looks normal but if i try to go anywhere on the internet - it tells me i am off line . 2.4 ghz wifi works just fine but the 5 ghz is broke. It took me a while to find this because I would auto switch to wifi at work and at home and didn't realize what was going on. Playstore would not download, app updates never came trhough. If I turned wifi off it all worked but then I am eating my data plan. Just an FYI to anyone having odd issues suddenly.

Weird. Mine still works fine on 5 GHz after 9.0.11 update (8/256 OP direct, totally stock unrooted).
Sent from my ONEPLUS A6013 using Tapatalk

Mines working fine here .. 9.0.11 unlocked/rooted
Sent from my [device_name] using XDA-Developers Legacy app

On 5ghz as well. I've had no issues at all after any of the updates. On 9.0.11, unlocked/rooted.

No issues with mine on 9.0.11.

I have they same problem!

I have the same issue.
For those, who say it works, turn mobile data off and try to browse on wifi 5ghz...

geminium said:
I have the same issue.
For those, who say it works, turn mobile data off and try to browse on wifi 5ghz...
Click to expand...
Click to collapse
5ghz working for me with mobile data off
Sent from my fajita using XDA Labs

geminium said:
I have the same issue.
For those, who say it works, turn mobile data off and try to browse on wifi 5ghz...
Click to expand...
Click to collapse
Just got the update minutes ago and upon reboot it immediately connected to my 5ghz wifi and works perfectly fine with mobile data on or off.

geminium said:
I have the same issue.
For those, who say it works, turn mobile data off and try to browse on wifi 5ghz...
Click to expand...
Click to collapse
Turned off mobile, still able to browse on wifi 5ghz.
Turned off mobile and wifi. Reconnected to wifi 5ghz. Still able to browse.
Turned on Airplane Mode. Reconnected to wifi 5ghz. Still able to browse.
Sorry. Can't reproduce issue.

For those that it works on 5 ghz - what band is your 5ghz on - if you check your wifi under network details see if it says 5 ghz or defaulting 2.4? (some people have combined wifi that will place you on what ever network is fastest) - also if you could show post your link speed (show on the Oneplus 6t under network details for wifi

Actually - I did a quick test and I could be incorrect. I set up a guest network with 5 ghz no password and got on it just fine and can pull 400 Mbs. My network password is complex so that might be what is causing the issues . I am going to experiment with a shorter password to see if that fixes it - but that would be a shame if that is the fix as it worked just fine before.

sharksfan7 said:
Turned off mobile, still able to browse on wifi 5ghz.
Turned off mobile and wifi. Reconnected to wifi 5ghz. Still able to browse.
Turned on Airplane Mode. Reconnected to wifi 5ghz. Still able to browse.
Sorry. Can't reproduce issue.
Click to expand...
Click to collapse
On tmobile, unlocked, flashed through twrp, no issue 5ghz as far as i can tell.

So I experimented more. Here are the results. No matter what I did to my internal wifi I could not get a connection on 5 Ghz. No issues on 2.4 with a long pw, a short pw- aes or tkip wpa or wpa2. But cannot, will not go anywhere on 5 ghz. Here is the odd thing. I can set up guest wifi on my router so I did. I set it up with no pw and boom, 2.4 g, 5 ghz1 and 5ghz2 - all of it. Then I turned on wpa/wpa2 and encryption (auto/aes/tkip) and set a password...and boom. Still working?? Exact same set up internal Wifi - nothing same issues. It's Bizarre. I turned off all the fancy settings for internal wifi like link sharing, fastest connection - I separeated them out to 2.4g/5G1/5g2 just like my guest and ...nothing. I can connect all day long but it just cannot get to anything on the internet. So for now I guess I am stuck using my guest network.

To the others who said they have the issue - what brand of router? - Mine is the TP-LINK AC5400

working fine here, verified that 5ghz is connected in settings

glenroebuck said:
For those that it works on 5 ghz - what band is your 5ghz on - if you check your wifi under network details see if it says 5 ghz or defaulting 2.4? (some people have combined wifi that will place you on what ever network is fastest) - also if you could show post your link speed (show on the Oneplus 6t under network details for wifi
Click to expand...
Click to collapse
In my network details it says frequency 5 GHZ and my Link speed is 866 Mbps.

glenroebuck said:
So I experimented more. Here are the results. No matter what I did to my internal wifi I could not get a connection on 5 Ghz. No issues on 2.4 with a long pw, a short pw- aes or tkip wpa or wpa2. But cannot, will not go anywhere on 5 ghz. Here is the odd thing. I can set up guest wifi on my router so I did. I set it up with no pw and boom, 2.4 g, 5 ghz1 and 5ghz2 - all of it. Then I turned on wpa/wpa2 and encryption (auto/aes/tkip) and set a password...and boom. Still working?? Exact same set up internal Wifi - nothing same issues. It's Bizarre. I turned off all the fancy settings for internal wifi like link sharing, fastest connection - I separeated them out to 2.4g/5G1/5g2 just like my guest and ...nothing. I can connect all day long but it just cannot get to anything on the internet. So for now I guess I am stuck using my guest network.
Click to expand...
Click to collapse
This sounds like it's a DCHP server issue with your router.

biohaz55 said:
This sounds like it's a DCHP server issue with your router.
Click to expand...
Click to collapse
can't be - dhcp is band agnostic and it works - I get an ip address on 2.4 and 5 ghz just cannot get anywhere on 5ghz when using my home internal router set up - plus when I set up guest network on the same router I am just fine. And it worked just fine before the latest Oxygen update (that and I have about 18 devices on wifi all working just fine - including my oneplus 6 running the same Oxygen update - ) Has to be a bug of some kind.

Same problem here, oneplus 6T and Oxygen 9.0.11. I have this bug since update from 9.0.10 to 9.0.11.
I'm not on TMobile (see on reddit about oneplus_6t_update_breaks_google_play_certification), i'm in Italy with TIM operator.
I have problems with Fastweb Fastgate Router (Askey RTV1907VW), wifi 5ghz is connected but i can't browse, i can't do a speedtest from App on OnePlus 6T, etc.
But now in my office, i have a Vodafone 5GHz router, and i don't have any issue!
Could be a problem of the "channel" for 5Ghz wifi connection?