@Jack_Thorne - is there anything interesting or notable in your router logs? As IPGentlemann noted above, you might check the antenna connections, but be careful, they are very fragile. I’m going to leave iwevent running on my machine to see if it captures anything interesting. I’ve seen other threads on here where people were having problems and disabling ax helped, but I haven’t run into that myself.
See these threads:
Looks like the ax setting was more related to slowness. Others mentioned potential router incompatibility. My routers are Asus and so far so good, fingers crossed.