A very quick post but one I thought I’d make after my Huawei Mate 20 Pro recently updated and decided that, even though the WiFi was working fine at home, it would frequently fall back to 4G / mobile data. Hopefully this post helps others who’ve been as infuriated as I have been trying to find a root cause to this!
Firstly, some specifications that apply to my particular problem:
- Phone
- Mobile Handset – Huawei Mate 20 Pro (O2 SIM)
- Model – LYA-L09
- Build – 9.1.0.358
- EMUI Version – 9.1.0
- Android Version 9
- WiFi
- Ubiquiti Unifi Controller on Ubuntu VM
- Ubiquiti UAP-AC-Lite
- Network Firewall & Security
- Sophos UTM
- Pi-Hole v4.3 running on Ubuntu VM
My phone would work absolutely fine on WiFi outside the home, but once I got home the device would regularly switch, and stay, on 4G while also still displaying the WiFi indicator in the status bar. The only time I’d really notice was when I tried to fling media across to my Chromecast. The WiFi connection had a strong signal, IP address and could ping anything on the local subnet via the WiFi connection. Anything remote would go via 4G.
A quick check on the Pi-hole blocked domains shown “e.crashlytics.com” blocked every minute or so, as well as “app-measurement.com”. I added both to the Pi-hole whitelist and several days later I’ve yet to get any recurrence of the problem so hopefully fixed.
