Have same issue on Xiaomi R3Gv1 (same SoC MT7621AT). Upgraded from 19 to 22.03.3 few days ago and now it hangs periodically: I see both WiFi but cannot connect, no reponse from wan side.
Sometimes I see:
[37083.302336] mt76x2e 0000:02:00.0: Firmware Version: 0.0.00
[37083.307868] mt76x2e 0000:02:00.0: Build: 1
[37083.312320] mt76x2e 0000:02:00.0: Build Time: 201607111443____
[37083.341107] mt76x2e 0000:02:00.0: Firmware running!
Features used:
- usb3 hdd
- samab4
- wireguard with 6 peers
- igmproxy
- mulicast-to-unicast on wifi 5Ghz
Router never hung running OpenWrt v19.