DM calls don't work at all

Summary

When I call my friend (or when my friend tries to call me) we just get yellow "connecting" for a moment, then it stops trying. We have also experienced a lot of lag and bad ping to the server, perhaps they are related. Server voice channels worked fine.

Steps to reproduce

1. Call a friend in DMs
2. Observe

Environment (optional)

We both used desktop on arch linux fully updated