An ASP.NET Core node which is not correctly leaving its Akka.NET Cluster

Console Output (from asp.net core worker node)

 INFO 13:53:51 [ 1] vices.WebApi.Program - samcs.WebApi starting
DEBUG 13:53:51 [ 1] vices.WebApi.Startup - Configure services
DEBUG 13:53:52 [ 1] vices.WebApi.Startup - Providing ActorSystem
DEBUG 13:53:52 [ 1] vices.WebApi.Startup - Initializing actor system with config from 'C:\Users\blankenaufulland\Source\Repos\samnext\foundation\samcs\src\samcs.WebApi\akka.hocon'
 INFO 13:53:52 [11] lassForStringSources - Starting remoting
 INFO 13:53:52 [ 3] lassForStringSources - Remoting started; listening on addresses : [akka.tcp://samgroup@127.0.0.1:12300]
 INFO 13:53:52 [ 8] lassForStringSources - Remoting now listens on addresses: [akka.tcp://samgroup@127.0.0.1:12300]
 INFO 13:53:52 [ 3] lassForStringSources - Cluster Node [akka.tcp://samgroup@127.0.0.1:12300] - Starting up...
 INFO 13:53:52 [11] lassForStringSources - Cluster Node [akka.tcp://samgroup@127.0.0.1:12300] - Started up successfully
DEBUG 13:53:52 [ 1] vices.WebApi.Startup - Configure
 INFO 13:53:52 [ 1] vices.WebApi.Startup - Activated actor system named 'samgroup'
DEBUG 13:53:52 [ 1] vices.WebApi.Program - Run webhost
Hosting environment: Development
Content root path: C:\Users\blankenaufulland\Source\Repos\samnext\foundation\samcs\src\samcs.WebApi
Now listening on: http://localhost:5000
Application started. Press Ctrl+C to shut down.
 INFO 13:53:53 [ 8] er.ClusterCoreDaemon - Welcome from [akka.tcp://samgroup@127.0.0.1:4053]
 INFO 13:55:24 [ 1] vices.WebApi.Startup - ASP.NET application stopped
DEBUG 13:55:24 [ 1] vices.WebApi.Startup - Marking ourself as DOWN
DEBUG 13:55:24 [ 1] vices.WebApi.Startup - Leaving cluster
DEBUG 13:55:24 [ 1] vices.WebApi.Startup - Waiting for ourself to be removed and terminated
 INFO 13:55:24 [ 3] r+RemotingTerminator - Shutting down remote daemon.
 INFO 13:55:24 [ 3] er.ClusterCoreDaemon - Marking node [akka.tcp://samgroup@127.0.0.1:12300] as [Down]
 INFO 13:55:24 [ 8] r+RemotingTerminator - Remote daemon shut down; proceeding with flushing remote transports.
ERROR 13:55:24 [ 3] ios.TcpClientHandler - Error caught channel [[::ffff:127.0.0.1]:12301->[::ffff:127.0.0.1]:4053](Id=ChannelId(1600056064))
System.ObjectDisposedException: Cannot access a disposed object.
Object name: 'System.Net.Sockets.Socket'.
   at System.Net.Sockets.Socket.Receive(Byte[] buffer, Int32 offset, Int32 size, SocketFlags socketFlags, SocketError& errorCode)
   at Helios.Channels.Sockets.TcpSocketChannel.DoReadBytes(IByteBuf buf)
   at Helios.Channels.Sockets.AbstractSocketByteChannel.SocketByteChannelUnsafe.FinishRead(SocketChannelAsyncOperation operation)
ERROR 13:55:24 [ 3] ios.TcpServerHandler - Error caught channel [[::ffff:127.0.0.1]:12300->[::ffff:127.0.0.1]:12311](Id=ChannelId(-18529280))
System.ObjectDisposedException: Cannot access a disposed object.
Object name: 'System.Net.Sockets.Socket'.
   at System.Net.Sockets.Socket.Receive(Byte[] buffer, Int32 offset, Int32 size, SocketFlags socketFlags, SocketError& errorCode)
   at Helios.Channels.Sockets.TcpSocketChannel.DoReadBytes(IByteBuf buf)
   at Helios.Channels.Sockets.AbstractSocketByteChannel.SocketByteChannelUnsafe.FinishRead(SocketChannelAsyncOperation operation)
 INFO 13:55:24 [ 3] .Actor.LocalActorRef - Message Disassociated from akka://samgroup/system/transports/akkaprotocolmanager.tcp.0/akkaProtocol-tcp%3a%2f%2fsamgroup%40127.0.0.1%3a4053-1 to akka://samgroup/system/endpointManager/reliableEndpointWriter-akka.tcp%3a%2f%2fsamgroup%40127.0.0.1%3a4053-1/endpointWriter/endpointReader-akka.tcp%3a%2f%2fsamgroup%40127.0.0.1%3a4053-1 was not delivered. 1 dead letters encountered.
 INFO 13:55:24 [ 3] teDeadLetterActorRef - Message DeadLetter from akka://samgroup/system/endpointManager/reliableEndpointWriter-akka.tcp%3a%2f%2fsamgroup%40127.0.0.1%3a4053-1 to akka://samgroup/deadLetters was not delivered. 2 dead letters encountered.
 INFO 13:55:24 [ 3] teDeadLetterActorRef - Message DeadLetter from akka://samgroup/system/endpointManager/reliableEndpointWriter-akka.tcp%3a%2f%2fsamgroup%40localhost%3a12309-2 to akka://samgroup/deadLetters was not delivered. 3 dead letters encountered.
 INFO 13:55:24 [ 3] .Actor.LocalActorRef - Message Disassociated from akka://samgroup/system/transports/akkaprotocolmanager.tcp.0/akkaProtocol-tcp%3a%2f%2fsamgroup%40%3a%3affff%3a127.0.0.1%3a12311-2 to akka://samgroup/system/endpointManager/reliableEndpointWriter-akka.tcp%3a%2f%2fsamgroup%40localhost%3a12309-2/endpointWriter/endpointReader-akka.tcp%3a%2f%2fsamgroup%40localhost%3a12309-1 was not delivered. 4 dead letters encountered.
 INFO 13:55:24 [ 3] .Actor.LocalActorRef - Message Disassociated from NoSender to akka://samgroup/system/transports/akkaprotocolmanager.tcp.0/akkaProtocol-tcp%3a%2f%2fsamgroup%40127.0.0.1%3a4053-1 was not delivered. 5 dead letters encountered.
 INFO 13:55:24 [ 3] .Actor.LocalActorRef - Message Disassociated from NoSender to akka://samgroup/system/transports/akkaprotocolmanager.tcp.0/akkaProtocol-tcp%3a%2f%2fsamgroup%40%3a%3affff%3a127.0.0.1%3a12311-2 was not delivered. 6 dead letters encountered.
 INFO 13:55:24 [ 3] .Actor.LocalActorRef - Message Disassociated from NoSender to akka://samgroup/system/transports/akkaprotocolmanager.tcp.0/akkaProtocol-tcp%3a%2f%2fsamgroup%40%3a%3affff%3a127.0.0.1%3a12311-2 was not delivered. 7 dead letters encountered.
 INFO 13:55:24 [ 3] .Actor.LocalActorRef - Message Disassociated from NoSender to akka://samgroup/system/transports/akkaprotocolmanager.tcp.0/akkaProtocol-tcp%3a%2f%2fsamgroup%40127.0.0.1%3a4053-1 was not delivered. 8 dead letters encountered.
 INFO 13:55:24 [ 3] teDeadLetterActorRef - Message DeadLetter from akka://samgroup/system/transports/akkaprotocolmanager.tcp.0 to akka://samgroup/deadLetters was not delivered. 9 dead letters encountered.
 INFO 13:55:24 [ 3] lassForStringSources - Remoting shut down
 INFO 13:55:24 [ 3] r+RemotingTerminator - Remoting shut down.
 INFO 13:55:24 [10] vices.WebApi.Startup - Shutting down actor system
DEBUG 13:55:24 [11] vices.WebApi.Startup - ActorSystem terminated
DEBUG 13:55:24 [ 1] vices.WebApi.Startup - ActorSystem termination signal received
 INFO 13:55:24 [ 1] vices.WebApi.Program - Webhost completed
Press [Enter] to exit

project.json (for versions)

{
  "dependencies": {
    "Akka": "1.1.0",
    "Akka.Cluster": "1.1.0",
    "Akka.Logger.log4net": "1.0.8",
    "Akka.Remote": "1.1.0",
    "Akka.Serialization.Wire": "1.0.9.227-beta",
    "Google.ProtocolBuffers": "2.4.1.555",
    "Helios": "2.1.1",
    "log4net": "2.0.5",
    "Microsoft.AspNetCore.Mvc": "1.0.0",
    "Microsoft.AspNetCore.Server.IISIntegration": "1.0.0",
    "Microsoft.AspNetCore.Server.Kestrel": "1.0.0",
    "Microsoft.Extensions.Configuration.EnvironmentVariables": "1.0.0",
    "Microsoft.Extensions.Configuration.FileExtensions": "1.0.0",
    "Microsoft.Extensions.Configuration.Json": "1.0.0",
    "Microsoft.Extensions.Logging": "1.0.0",
    "Microsoft.Extensions.Logging.Console": "1.0.0",
    "Microsoft.Extensions.Logging.Debug": "1.0.0",
    "Newtonsoft.Json": "9.0.1",
    "samcs.Shared": "1.0.0-*",
    "samcs.Shared.ApiClient": "1.0.0-*"
  },
  "tools": {
  },
  "commands": {
    "web": "Microsoft.AspNet.Server.Kestrel --server.urls=http://*:8999/"
  },
  "frameworks": {
    "net461": { }
  },
  "buildOptions": {
    "emitEntryPoint": true,
    "preserveCompilationContext": true,
    "copyToOutput": [
      "akka.hocon",
      "appsettings.json"
    ]
  },
  "runtimeOptions": {
    "gcServer": true
  },
  "publishOptions": {
    "include": [
      "wwwroot",
      "Views",
      "akka.hocon",
      "appsettings.json",
      "web.config"
    ]
  },
  "scripts": {
    "postpublish": [ "dotnet publish-iis --publish-folder %publish:OutputPath% --framework %publish:FullTargetFramework%" ]
  }
}

Startup.cs

public class Startup
{
    private static readonly log4net.ILog log = log4net.LogManager.GetLogger(System.Reflection.MethodBase.GetCurrentMethod().DeclaringType.FullName);
    private ActorSystem actorSystem;
    private readonly ManualResetEvent asTerminatedEvent = new ManualResetEvent(false);

    public Startup(IHostingEnvironment env)
    {
        var builder = new ConfigurationBuilder()
            .SetBasePath(env.ContentRootPath)
            .AddJsonFile("appsettings.json", optional: true, reloadOnChange: true)
            .AddJsonFile($"appsettings.{env.EnvironmentName}.json", optional: true)
            .AddEnvironmentVariables();
        Configuration = builder.Build();
    }

    public IConfigurationRoot Configuration { get; }

    public void ConfigureServices(IServiceCollection services)
    {
      //...
    }

    public void Configure(IApplicationBuilder app, IHostingEnvironment env, ActorSystem actorSystem, ILoggerFactory loggerFactory, IApplicationLifetime applicationLifetime)
    {
        applicationLifetime.ApplicationStopped.Register(HandleStopped);
        // ...
    }

    private void HandleStopped()
    {
        log.Info("ASP.NET application stopped");
        if (this.actorSystem != null)
        {
            var cluster = Akka.Cluster.Cluster.Get(this.actorSystem);
            cluster.RegisterOnMemberRemoved(MemberRemoved);

            //log.Debug("Marking ourself as DOWN");
            //cluster.Down(cluster.SelfAddress);

            log.Debug("Leaving cluster");
            cluster.Leave(cluster.SelfAddress);
            log.Debug("Waiting for ourself to be removed and terminated");
            this.asTerminatedEvent.WaitOne();
            log.Debug("ActorSystem termination signal received");
        }
        else
        {
            log.Debug("ActorSystem not initialized so no termination sequence");
        }
    }

    private async void MemberRemoved()
    {
        log.Info("Shutting down actor system");
        await this.actorSystem.Terminate();
        log.Debug("ActorSystem terminated");
        this.asTerminatedEvent.Set();
    }
}