That kernel warning suggests that something is on the Wifi side (rax0 interface is Wifi 5Ghz in uci config).
For the sake of test I switched to 40Mhz channel width I am not getting ping losses when doing speedtest. I wouldn’t mind using 40Mhz but with 40Mhz I am getting:
- Higher ping latency during test (300ms vs 100ms on 80Mhz channel)
- Lower throughput - on 80Mhz I am getting my full 250Mbps broadband, on 40Mhz - 150Mbps max.
Perhaps that is mt798112 drivers issue? Is there a newer available? (maybe some more or less stable beta releases of your firmware?)