Element, no calls possible

I have some trouble to make a call with Element. If I try
to make a call, it shows me ringing, but on the other side,
there is nothing. Also, if somebody makes a call to me, it is
ringing on my phone, but when I try to answer the call, nothing happend.

The other functions of Element are running normal. I can chat
with others or share photos and videos. Only calling doesnt work.

My questions are, if somewhere a good manual/faq exists for
aliendalvik for the JollaPhone? How to debug this?

I was searching a lot for a good wiki, blog, manuals etc. for
Sailfish, but I couldn’t find much. Maybe you know some URLs
for me for reading?

Thanks.

Sailfish OS 4.1.0.24 (Kvarken)

uname -a
Linux localhost 4.4.194 #1 SMP PREEMPT Thu Feb 25 06:34:14 UTC 2021 armv8l

[ro.product.system.model]: [AlienDalvik on Jolla Devices]
[ro.product.model]: [Xperia XA2 (AOSP)]
[ro.product.name]: [aosp_h3113]
[ro.system.build.date]: [Thu Apr 22 18:27:53 UTC 2021]

dumpsys package im.vector.app | grep versionName
versionName=1.1.9

Unfortunately this is a know problem, not only for Element, but also for other Android Apps offering Video Calls.
I am also using Element here, and Videocalls work when I disable Wifi and use 4G.

thanks for your answer.

Never tried the Video-Call before, I meant the Call Funktion. both are not working. Not with wifi, nor LTE.

Had the same problem with Aliendalvik + Jitsi app: no audio in both directions.

I made only a few small tests now, and it seems, that Element uses the own included mediaplayer for playing videos in rooms. And at this point sound is working.

But in the moment, there is a lot of stuff running i do not understand at the phone. Unfortunately there is systemd, which makes everything a bit harder for me to puzzle out. I suspect some firewall-rules for the misconnection, not really an audio fault.