Slow and disconnect

I encountered slowness and disconnections.
I have follow Quick guide install (Harvester etc…), my system is corei7 32GoRam 512SSD 100MB/s SDSL.
I have :
> some users connecting from LAN with DNS = LocalIP
> some users connecting from internet with DNS = PublicIP

I try to configure config.js with lower resolution but no…

Can You help me ?

Are you seeing any errors in your log files?

Are they connecting via the apps, or via a browser?

Both, from app and browsers.
try with
> only chrome users
> mix of browsers/app
> only from internet
> only from lan
same pb .

short exemple of my logs :

2020-04-03 09:49:18.914 INFOS: [465] [confId=56779e8e4c1f47dd gid=ff7a09 stats_id=Everette-J9D conf_name=bddpi ufrag=8ssd61e4vn31cq epId=05a144fc local_ufrag=8ssd61e4vn31cq] ConnectivityCheckClient.processTimeout#860: timeout for pair: LOCALjitsiIP:10000/udp/host -> LOCALpcIP:52565/udp/prflx (stream-05a144fc.RTP), failing.

2020-04-03 10:00:40.464 INFOS: [456] [confId=56779e8e4c1f47dd gid=ff7a09 stats_id=Turner-VLI componentId=1 conf_name=bddpi ufrag=3k7of1e4vn31f1 name=stream-55bc5355 epId=55bc5355 local_ufrag=3k7of1e4vn31f1] MergingDatagramSocket$SocketContainer.runInReaderThread#770: Failed to receive: Socket closed

2020-04-03 14:45:37.311 INFOS: [19] Videobridge.createConference#326: create_conf, id=13509f66f98229fc gid=null logging=false
2020-04-03 14:45:37.314 INFOS: [19] Health.doRun#294: Performed a successful health check in 4ms. Sticky failure: false

I replace the true IP by :
> LOCALjitsiIP :Local ip of my jitsi server
> LOCALpcIP : ip of a computer inside lan

Thank you

Resolution change in interface_config.js should be picked up by those using the browser, but won’t be respected by those using the app, as I understand it.

Is your jitsi server behind NAT?

Yes the server is behin nat.
I follow the advanced configuration in the quick install guide.

When I see connection in my firewall, Is see connection from lan users on port 10 000 to LOCALjitsiIP (allowed) and PUBLICjitsiIP (blocked to prevent hairpinning NAT). It’s strange…
Can that be it?