Dramatic Wifi slowdown 19.3-Matrix

I’m on an S905X3 (X96 Max Plus 4 or 2 / 64). Yes, I know…

Everything used to work fine (except for the 4GB vs 2GB RAM issue) until a few days ago the Wifi (2.4 GHz) connection slowed down dramatically, from >10 Gbps to <1Gbps. I’m not sure if it happened when updating to 19.3. Most like it has already been 19.3 (unless the update really came a few days ago?)

I know my box is a shame but I’m kindly asking for help to diagnose and hopefully fix the problem. It used to work, so I’m hoping it can work again. Thank you!

Thanks for the reply and here we go:
http://ix.io/3FTR

After a reboot today the problem miraculously went away. I’ll come back if it reoccurs.

The problem is back. After rebooting a few times, it eventually goes away, then comes back again. Download speed is around 0.1 Mbps. The other devices in the same room have good wifi connection.