Video/sound lost and unable to join again

I’m using jitsi on twenty instances EC2, type t3a medium, one server for one classroom, usually 25 students and a teacher. We are using our web interface based on lib jitsi meet.

It works really fine and Jitsi is really awesome for us, but some times I have this logs:

JVB 2020-01-31 09:37:23.296 SEVERE: [11001] org.jitsi.impl.neomedia.RTPConnectorOutputStream.log() Failed to send a packet to target /X.X.X.X:53371:java.io.IOException: No active socket.

When it happens, the student using this IP have generally sound freezed, sometimes vidéo.

Student seems to not change public IP, the teacher has a really good connexion with latency under 10ms et no packet losss.

Conference is also blocked for newcomers, old ones can continue see video/sound without problems.

I’m using jicofo 1.0-481-1, jitsi-meet 1.0.3936-1, jitsi-meet-prosody 1.0.3577-1, jitsi-meet-web 1.0.3577-1, jitsi-meet-web-config 1.0.3577-1 and jitsi-videobridge 1124-1

Do you know what can be the cause of it ? What can I try ?

Thanks.

Try updating to the latest version of jitsi-videobridge and see if the problem persists.

Boris