Sporadical network disconnect

[VasiliyM6]

I've bought recently AS5304T. A couple of days ago I noticed that NAS disappears from the network - it stops streaming video and it's impossible to log into ADM. But then it comes back on.
I've checked log and fould several couples of messages like
"INFO","28-03-2021 19:26:43","SYSTEM","[Network] LAN1 was plugged in."
"INFO","28-03-2021 19:26:39","SYSTEM","[Network] LAN1 was unplugged."
It takes 5-10 seconds, but during that time it loses the network and the movie is interrupted or freezes.
I've replaced patch-cord, changed network socket in router - but it doesn't help.
What's even stranger is that it only happens in the evening. Today I put it to "stress test": all day streaming 4K video, downloading and distributing torrents, recording from 2 cameras - everything worked perfectly. But after 10 pm it started again. What can be the reason? How can it be fixed?

System log extract

2021-03-29_22-57-09.jpg (176.26 KiB) Viewed 2795 times

[orion]

Sounds weird, "after 10pm". I think you should check NAS processes (after 10pm) and router related stuff (adding a switch between NAS and router?).

[VasiliyM6]

Sorry for delay with answer. Yes, partially it caused by issue with router - but it was fixed. there were not many applications running on NAS - utorrent and UPnP Media server 1. I suspected that may be utorrent caused such NAS behavior and now I stop use it.
So, will try to monitor more precisely sist of services and applications running on NAS.

[mss]

Similar situation. But I could not find a connection with the time of day.
Updated to AS6602T (AS-602T peacefully reposed after 7 years of blameless service) on which ADM 3.5.5.RFC3 is installed.
From applications only utorrent and exFAT driver. The network was constantly falling off.
Just yesterday I stopped utorrent.
Installed qBittorrent Parick (plus Docker-ce and Portainer CE).
Almost a day as "not a single gap" ...
I can't attach a log file.
And there is a switch between the NAS and the router
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Похожая ситуация. Но с временем суток связи не нашёл.
Обновился на AS6602Т (AS-602Т мирно почил после 7 лет беспорочной службы) на котором установлена ADM 3.5.5.RFC3.
Из приложений только utorrent и ехFAT driver. Сеть постоянно отваливалась.
Буквально вчера остановил utorrent.
Установил qBittorrent Parick'а (к нему ещё Docker-ce и Portainer CE).
Без малого сутки как "ни единого разрыва"...
Не получается прикрепить файл с журналом.
И между NAS и роутером есть свитч