JellyFin prevent HDD hibernation on Synology NAS

[tkrejci]

I'm facing exactly the same issue. The Jellyfin log is full of entries like:
[2024-11-29 08:21:27.817 +00:00] [INF] [34] Emby.Server.Implementations.ScheduledTasks.TaskManager: "Prohledat knihovnu médií" Completed after 0 minute(s) and 12 seconds
[2024-11-29 08:22:03.218 +00:00] [INF] [102] Emby.Server.Implementations.Session.SessionWebSocketListener: Sending ForceKeepAlive message to 1 inactive WebSockets.
[2024-11-29 08:25:39.217 +00:00] [INF] [115] Emby.Server.Implementations.Session.SessionWebSocketListener: Sending ForceKeepAlive message to 1 inactive WebSockets.
[2024-11-29 08:28:27.217 +00:00] [INF] [70] Emby.Server.Implementations.Session.SessionWebSocketListener: Sending ForceKeepAlive message to 1 inactive WebSockets.
[2024-11-29 08:31:15.218 +00:00] [INF] [35] Emby.Server.Implementations.Session.SessionWebSocketListener: Sending ForceKeepAlive message to 1 inactive WebSockets.
[2024-11-29 08:34:03.219 +00:00] [INF] [100] Emby.Server.Implementations.Session.SessionWebSocketListener: Sending ForceKeepAlive message to 1 inactive WebSockets.
[2024-11-29 08:37:39.218 +00:00] [INF] [96] Emby.Server.Implementations.Session.SessionWebSocketListener: Sending ForceKeepAlive message to 1 inactive WebSockets.

I have the suspicion that logging is the thing making the HDDs alive and prevents theirs hybernation.