http exception, error log bigger than 100 MB, server not working properly

[amarok 0]

Since yesterday my server is not working properly anymore. I did not change anything in the configuration of my server, but my emby installation is laggy and sometimes unresponsive, sometimes the web app for example is not loading at all. When I click restart in the menu of the tray icon the server is not responding as well and I have to kill it with the task manager. After a restart the server is working properly for about 10 minutes, then the  problems start again.

 

The error log is growing very fast, so yesterday for half of the day the log was over 100MB big, also this error is repeating itself very often:

 

*** Error Report ***
Version: 4.3.1.0
Command line: C:\Users\XAdmin\AppData\Roaming\Emby-Server\system\EmbyServer.dll
Operating system: Microsoft Windows NT 6.2.9200.0
64-Bit OS: True
64-Bit Process: True
User Interactive: True
Runtime: file:///C:/Users/XAdmin/AppData/Roaming/Emby-Server/system/System.Private.CoreLib.dll
Processor count: 8
Program data path: C:\Users\XAdmin\AppData\Roaming\Emby-Server\programdata
Application directory: C:\Users\XAdmin\AppData\Roaming\Emby-Server\system
MediaBrowser.Model.Net.HttpException: MediaBrowser.Model.Net.HttpException: Connection to https://fcm.googleapis.com/fcm/send timed out
---> System.Threading.Tasks.TaskCanceledException: The operation was canceled.
   at System.Net.Http.ConnectHelper.ConnectAsync(String host, Int32 port, CancellationToken cancellationToken)
   at System.Net.Http.HttpConnectionPool.ConnectAsync(HttpRequestMessage request, Boolean allowHttp2, CancellationToken cancellationToken)
   at System.Net.Http.HttpConnectionPool.CreateHttp11ConnectionAsync(HttpRequestMessage request, CancellationToken cancellationToken)
   at System.Net.Http.HttpConnectionPool.GetHttpConnectionAsync(HttpRequestMessage request, CancellationToken cancellationToken)
   at System.Net.Http.HttpConnectionPool.SendWithRetryAsync(HttpRequestMessage request, Boolean doRequestAuth, CancellationToken cancellationToken)
   at System.Net.Http.RedirectHandler.SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
   at System.Net.Http.DecompressionHandler.SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
   at System.Net.Http.HttpClient.FinishSendAsyncUnbuffered(Task`1 sendTask, HttpRequestMessage request, CancellationTokenSource cts, Boolean disposeCts)
   at Emby.Server.Implementations.HttpClientManager.CoreHttpClientManager.SendAsyncInternal(HttpRequestOptions options, String httpMethod)
   --- End of inner exception stack trace ---
   at Emby.Server.Implementations.HttpClientManager.CoreHttpClientManager.SendAsyncInternal(HttpRequestOptions options, String httpMethod)
   at Emby.Server.Implementations.HttpClientManager.CoreHttpClientManager.SendAsync(HttpRequestOptions options, String httpMethod)
   at Emby.Server.Implementations.Session.FirebaseSessionController.SendMessage[T](ReadOnlyMemory`1 name, String messageId, T data, CancellationToken cancellationToken)
   at Emby.Server.Implementations.Session.SessionManager.SendMessageToSession[T](SessionInfo session, ReadOnlyMemory`1 name, T data, CancellationToken cancellationToken)
   at Emby.Server.Implementations.Session.SessionManager.<>c__DisplayClass116_1`1.<<SendMessageToUserDeviceAndAdminSessions>b__2>d.MoveNext()
Source: Emby.Server.Implementations
TargetSite: Void MoveNext()
InnerException: System.Threading.Tasks.TaskCanceledException: The operation was canceled.
Source: System.Private.CoreLib
TargetSite: Void Throw()
   at System.Net.Http.ConnectHelper.ConnectAsync(String host, Int32 port, CancellationToken cancellationToken)
   at System.Net.Http.HttpConnectionPool.ConnectAsync(HttpRequestMessage request, Boolean allowHttp2, CancellationToken cancellationToken)
   at System.Net.Http.HttpConnectionPool.CreateHttp11ConnectionAsync(HttpRequestMessage request, CancellationToken cancellationToken)
   at System.Net.Http.HttpConnectionPool.GetHttpConnectionAsync(HttpRequestMessage request, CancellationToken cancellationToken)
   at System.Net.Http.HttpConnectionPool.SendWithRetryAsync(HttpRequestMessage request, Boolean doRequestAuth, CancellationToken cancellationToken)
   at System.Net.Http.RedirectHandler.SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
   at System.Net.Http.DecompressionHandler.SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
   at System.Net.Http.HttpClient.FinishSendAsyncUnbuffered(Task`1 sendTask, HttpRequestMessage request, CancellationTokenSource cts, Boolean disposeCts)
   at Emby.Server.Implementations.HttpClientManager.CoreHttpClientManager.SendAsyncInternal(HttpRequestOptions options, String httpMethod)

The emby installation is running in a windows installation behind a Reverse Proxy, but this should not be the problem, because it was running in this setting for over 2 years perfectly and I did not change any settings in the last days.

embyserver.txt