I mainly use Wifi Calling. I force it setting “plane mode” and then turning on the wifi.
I noticed that sometimes, for any reason, when I try to give a call, there is first no tone, and then I am connected directly to the answering machine of my correspondent.
I notice that sometimes, in this case, I can give the call if I turn on the VPN.
Is there really a link? Or is it just because I tried a second time
If the VPN indeed enables the call, what does that mean? Is it a matter of network?
Can You provide more specific info on what kind of “VPN” are you using? Advanced Privacy - hide my IP? some external service? some sort of tracker blocking or firewall-App?
VPN connections (especially external services) sometimes take a moment until fully ready - I imagine that when You are quick with dialing after switching VPN on: it might still connect correctly but the ringtone might simply get lost somehow (?)
I am sorry but my knowledge on wifi calling is pretty limited (rather non existing), I could only speculate on the VPN part… Does the issue depend on duration after VPN activation?
I am sure there’s someone more knowlegeable around.
PS have you checked with proton if that is maybe a known issue for wifi calls via their VPN? edit: sorry I thoroughly misread your issue description even though it is wrapped up in the title - as the wifi call works bettter with VPN ON and has these issues w/o VPN it seems to rather be an issue with the general network connection (wifi) and/or its provider and not with VPN I would guess (?)
wificall is ipsec on udp to destination ports 500 + 4500 - so if @ThomaM is in a network that does anything to these flows he’ll have problems. When it is your home network, check the router config for port fitlering and network address translation (nat) settings - https://www.networkcomputing.com/networking/your-network-optimized-wifi-calling
Interesting when in the same network it sometimes works, sometimes doesn’t. Is the device connected to a wifi repeater then?
Enabling a vpn will free you of the packet filter rules the network imposes. Of course this can help with networks you can’t control
- as the wifi call works bettter with VPN ON and has these issues w/o VPN it seems to rather be an issue with the general network connection (wifi) and/or its provider and not with VPN I would guess (?)