Slow Wifi with brand new Surface Book 2!!!

I think your guess is right on. If I'm not mistaken the Bluetooth and Wi-Fi radios are a single combined unit. I've also isolated flickering on an external monitor to be caused by Bluetooth even though it's wired to the dock.

I have been trying to figure this out all day...have run 100 speed tests...

Interesting enough, when I turn bluetooth off, my speeds are fine 100% of the time. When I turn it back on, they slow, but some times they are just a tad below my top speed and some times very slow. Now of course that could be a complete coincidence. I had a hypothesis that when I moved my pen to the other room maybe it was trying to connect to it via bluetooth and due to the distance it was straining. That is the only other thing *I* changed other than updating to 1809 and the latest SB2 drivers (used to keep pen close/attached but moved it to a room down the hall the other day). I think its related to bluetooth/power management/interference but trying to narrow it down is proving difficult. Of course it might be external interference from a neighbor but very odd that when I turn bluetooth off, so far every time, I get top speeds...

And there is more joy ..... earlier I posted that to get round this ridiculous problem I purchased a TP-LINK ARcher Wifi Dongle. Plugged it into my surface doc . Guess what its keeps dropping out . Like its powered off , but its not, green light is on. So took it out and plugged into SB2 itself. Never drops ...... Great even the dock is useless. THGis is so unacceptable.

Yay, Microsoft managed to break something yet again!

I was running with zero issues related to WiFi prior (just a slew of other issues ha). Just installed 1809 and latest Surface Book 2 firmware updates/drivers. Noticed computer is lagging, primarily when browsing the internet. Ran a speed test. Turns out that I am getting a fraction of the speed I should be, standing right next to router. Running speed test on other devices shows full speeds. I am talking as low as 0.15 mbps with full signal. Switching to 5ghz I get 30mbps on a partial signal which is full speed of the connection at the location I am presently at. Switch back to 2.4ghz and I see slow speeds.

Interesting enough, and could have been coincidence, but when I opened task manager I saw delivery optimization was using a lot of bandwidth on the receive side. I am fully updated, have no updates pending, and have the Windows Update Delivery Optimization settings disabled so I do not know why Delivery Optimization is even running in the background?

In any event, my SB2 is basically unusable for me because where I sit there is only 2.4ghz. The WiFi worked fine before these updates. I am also now getting a new BSOD. Thank you Microsoft for your excellent products!

I agree but also feel it wont fix anything as you will still have the crappy Wifi adapter. Its not changed. BUTR maybe if more of us return for this issue it will wake MSoft up.