Strange behavior of 5Ghz channel

[christer12]

I have chosen channel 40 in 5Ghz spectrum, but after a day RAX40 always changes router to a worse channel 36 and then the speed drops from 2,4 Gbps to 1,2 Gbps on Wifi 6.

Is this a bug?

[plemans · Accepted solution]

Looks like that adapter is based off the intel chipset. Not sure how frequently tp-link updates it but intel updates theirs quite frequently.

another though is how far from the router are you? 

Again, you might still be broadcasting on that channel as well but dropping from 160hz to 80hz width. potentially due to distance, interference, etc. 

[plemans]

When you're running 160hz channels, you choose a "primary" channel. Because of overlap from the 160hz you get additional channels in use. If I select primary channel 36 with mine, it uses channel 36, 40, 44, 48. If I switch to channel 40, it uses 36,40,44,48 but the channel 40 is primary. 

How are you testing this? What device/devices?

Are you doing channel scanning to see if its not broadcasting or how exactly are you determining what you're getting? 

What region are you in? Certain channels are DFS and the router has to auto switch off them if a signal is detected. 

[christer12]

I live in Norway and use TP-Link Archer TX3000E on my intel X99 desktop. I used WifiAnalyser to find what channel is best for me, but it auto switching anyway

[plemans · Accepted solution]

Looks like that adapter is based off the intel chipset. Not sure how frequently tp-link updates it but intel updates theirs quite frequently.

another though is how far from the router are you? 

Again, you might still be broadcasting on that channel as well but dropping from 160hz to 80hz width. potentially due to distance, interference, etc. 

[christer12]

Yes, it's intel AX200 and I use latest driver 21.60.2.. I'm 3 meters from the router