Big Sur: slow wifi, socket error, etc - need help

[Kulfon]

Folks, ever since I have installed Bog Sur I have this weird internet issue.
Internet is there, it works, but it is super slow. I am not able to download anything, the speed is 5 KB/S and my internet is 150 GB/S.
It was all flying before Big Sur. I tried doing Speed Test and I got this error message: "A socket error occurred during the download test".
What can be done to diagnose and fix? Anyone with similar issue?
Thanks!

 

[Kulfon]

Folks, noone with the issue? Any ideas where to try?

 

[IowaLynn]

I assume you tried the basics.
Unplug modem and router for 5 minutes
Check your cables
See if there is a firmware update on router
If possible try Ethernet

I think you mean 150 Mb ?
How old is router?
Talked to ISP?
If you go back to Catalina everything’s ok?
What devices and Mac are you even using?
Do you have a spare older modem/router to test with? Though an ISP may need to add/activate if it sees a change.
Log into your router and look for new firmware and settings. Hopefully it is still being supported. Many stop getting support after a few yrs.

 

[TimManzana]

my wifi connection is extremely slow in my 2020 MacBook Pro with Big Sur, my connection is Fiber with 2 google wifi nods and doing a speed test in other devices I'm getting 300+Mbps, my MacBook is getting no more than 8Mbps, any suggestion?

 

[sn00p]

I'm having this issue, although not as slow as that, I get about 10-20Mbps. If I boot the machine into safe mode, the WiFi behaves as expected 350-400Mbps, boot back into normal mode and I barely hit 20Mbps if I'm lucky.

I've tried all the workarounds that I've seen suggested in various places with people experiencing exactly the same issue.

I'm currently having to plugin a 10Gbe adaptor into my MBP to get proper speeds and so I can access my development machine in my office without horrible lag.