I'm running the latest version of GrapheneOS on a Pixel 4a. I've also installed the latest version of the Cheogram app and configured it with a VOIP number from JMP.Chat. Most of the time this works pretty well, but sometimes no notification comes through for an incoming call.
The Cheogram app has been granted all of its requested permissions, and the app battery usage has been set to unrestricted. If I wake the screen while the phone is supposed to be ringing, the notification will pop up, and the phone will start ringing.
If I ping the phone's Wi-Fi IP from another device while the phone is supposed be ringing, the notification will also pop up, and the phone will start ringing. No pings are ever lost either. Generating pings from the phone with the "Keep it up" app doesn't seem to make a difference though.
When I contacted Cheogram support, they replied:
We have noticed an issue in GOS that stops the network connectivity with background processes when the screen goes to sleep. This was not present in versions before about 5-6 months ago, but now seems to be persistent. You may need to report this issue to the GOS devs for a fix or potential workarounds.
Is this currently a known issue in GrapheneOS?
Is there any other information I can provide or are there any other settings I should change?
On my home Wi-Fi I can put the phone on a static IP and ping it every minute or so, but this isn't feasible for other Wi-Fi networks. Are there any other potential workarounds I should try? Thanks!