I recently got a new router because my old one died. We have a lot of networked devices (personal phones, work phone, laptop, kindle, kid's school tablet, thermostat, 2 chromecasts, etc...). Right around the same time, the personal phones (2 Pixel 4a) had a system update. And i noticed the internet went to crap on the phones, but only on wifi, was just fine on mobile.
At first i blamed it on the system update because literally every other device i tried in the house was fine. But then i tried the laptop, and it was having the same issue. Googling suggested the network card in laptop was very old so i bought a USB network card/antenna and it was fine after that. Then, my mom was visiting one day and brought her much newer laptop, but she had the same issue, and plugging in that USB antenna solved it. And then i took my phone to a friend's house and the wifi was fine. And also my phone was fine on my mom's apartment wifi.
So that has now firmly convinced me it's the new router. It's a pretty fancy one, supports two 5Ghz and two 2Ghz wifi channels, lots of configuration options. My guess is that there is some option turned on that doesn't work with Pixel 4a wifi. Any ideas what it could be?
What i mean by crappy wifi internet: pages take a minute to load that on other wifi pr mobile take seconds. YouTube preview images likewise. But if i go to speedtest website, it tells me i have 200MB down and 20 up.