Ignore more signalr non-errors

src/NzbDrone.Host/Owin/NlogTextWriter.cs

@@ -59,15 +59,23 @@ namespace NzbDrone.Host.Owin
                 return LogLevel.Trace;
             }
             
-            if (lower.Contains("signalr") && lower.Contains("an operation was attempted on a nonexistent network connection"))
+            if (lower.Contains("signalr"))
+            {
+                if (lower.Contains("an operation was attempted on a nonexistent network connection"))
+                {
+                    return LogLevel.Trace;
+                }
+
+                if (lower.Contains("the network connection was aborted by the local system"))
                 {
                     return LogLevel.Trace;
                 }
 
-            if (lower.Contains("signalr") && lower.Contains("the network connection was aborted by the local system"))
+                if (lower.Contains("the socket has been shut down"))
                 {
                     return LogLevel.Trace;
                 }
+            }
 
             return LogLevel.Error;
         }