Fixed: Authentication on DSM 7

closes #3943
ref #4313

src/NzbDrone.Core/Download/Clients/DownloadStation/Proxies/DiskStationProxyBase.cs

@@ -130,7 +130,7 @@ namespace NzbDrone.Core.Download.Clients.DownloadStation.Proxies
         {
             var authInfo = GetApiInfo(DiskStationApi.Auth, settings);
 
-            var requestBuilder = BuildRequest(settings, authInfo, "login", 2);
+            var requestBuilder = BuildRequest(settings, authInfo, "login", authInfo.MaxVersion >= 7 ? 6 : 2);
             requestBuilder.AddQueryParam("account", settings.Username);
             requestBuilder.AddQueryParam("passwd", settings.Password);
             requestBuilder.AddQueryParam("format", "sid");