Yep,
Confirming the ngfd being the culprit on C2.
It used up to 12.8% CPU constantly when hung up.
If so, no alarm, no notification sound, no vibra, no…
An absolute unreliable phone then
Fixed it with a script put into /etc/profile.d which checked the CPU usage being greater than 10% and killing, restarting ngfd.
Unfortunately I fiddled with the device and the fstab file and had a boot loop. Now it is on the way back… Together with the script but it was only a few ps aux grep cut xargs and if commands 