Cannot hear a random participant if more than 3 people joined a call

Hello!

I have faced with an issue: when more than 3 participants join a group call a few minutes later a random participant cannot hear another random (but not all) participant.

I have searched a bit and found a few similar issues. The recommendation is to configure a High-Performance backend to resolve the issue. But it has already been installed and running (at least the admin page says so) as a part of the AIO package.

I haven’t changed any settings regarding the Talk and expected it to work out-of-the-box as expected in the AIO package.

The server has 8Gb of RAM and 8 cores (it is a virtual machine). The server connected to a dedicated 1 Gbps port. Both 3478/TCP and 3478/UDP ports are open and forwarded to the Nextcloud server directly. The Nextcloud Web-app is sitting behind a reverse proxy (Nginx proxy manager).

I kindly ask help me to resolve the issue.

Nextcloud version: Nextcloud AIO v11.5.0
Talk Server version: 21.1.3
Custom Signaling server configured: no
Custom TURN server configured: no (only the one included in the AIO)
Custom STUN server configured: no (only the one included in the AIO)

In case the web version of Nextcloud Talk is involved:
Operating system: Windows 10, Windows 11, Ubuntu 25.04
Browser name and version: Firefox 141.0.3, Chrome

The issue you are facing:
See above.

Is this the first time you’ve seen this error? Yes

Steps to replicate it:

  1. Connect to a call
  2. Wait for more than 3 participants to join
  3. Wait ~30-300 sec.
  4. Observe the issue: a random participant cannot hear another random participant (but not all the participants).

The output of your Nextcloud log in Admin > Logging or errors in nextcloud.log in /var/www/:

N/A

The output of your Apache/nginx/system log in /var/log/____:

N/A

Your browser log if relevant (javascript console log, network log, etc.):

N/A