diff --git a/v2rayN/v2rayN/Forms/MainForm.cs b/v2rayN/v2rayN/Forms/MainForm.cs
index 6e88ea8000..cb839d46f0 100644
--- a/v2rayN/v2rayN/Forms/MainForm.cs
+++ b/v2rayN/v2rayN/Forms/MainForm.cs
@@ -129,7 +129,7 @@ private void MainForm_FormClosing(object sender, FormClosingEventArgs e)
             {
                 e.Cancel = true;
 
-                statistics?.saveToFile();
+                statistics?.SaveToFile();
 
                 HideForm();
                 return;
@@ -137,7 +137,7 @@ private void MainForm_FormClosing(object sender, FormClosingEventArgs e)
             if (e.CloseReason == CloseReason.ApplicationExitCall)
             {
                 ConfigHandler.SaveConfig(ref config);
-                statistics?.saveToFile();
+                statistics?.SaveToFile();
                 statistics?.Close();
             }
         }
@@ -168,7 +168,7 @@ protected override void WndProc(ref Message m)
                     Utils.SaveLog("Windows shutdown UnsetProxy");
                     //CloseV2ray();
                     ConfigHandler.ToJsonFile(config);
-                    statistics?.saveToFile();
+                    statistics?.SaveToFile();
                     ProxySetting.UnsetProxy();
                     m.Result = (IntPtr)1;
                     break;
diff --git a/v2rayN/v2rayN/Global.cs b/v2rayN/v2rayN/Global.cs
index 8bbab44b7b..eb54a2be27 100644
--- a/v2rayN/v2rayN/Global.cs
+++ b/v2rayN/v2rayN/Global.cs
@@ -146,7 +146,7 @@ class Global
         public const string InboundProxyTagName = "proxy";
         public const string Loopback = "127.0.0.1";
         public const string InboundAPIProtocal = "dokodemo-door";
-        public const uint InboundAPIPort = 10805;
+     
         public enum StatisticsFreshRate
         {
             quick = 1000,
@@ -185,6 +185,11 @@ public enum StatisticsFreshRate
         /// </summary>
         public static int pacPort { get; set; }
 
+        /// <summary>
+        ///  
+        /// </summary>
+        public static int statePort { get; set; }
+
         #endregion
 
 
diff --git a/v2rayN/v2rayN/Handler/StatisticsHandler.cs b/v2rayN/v2rayN/Handler/StatisticsHandler.cs
index ba2e948d83..d25c23b09f 100644
--- a/v2rayN/v2rayN/Handler/StatisticsHandler.cs
+++ b/v2rayN/v2rayN/Handler/StatisticsHandler.cs
@@ -1,16 +1,13 @@
-using System;
+using Grpc.Core;
+using System;
 using System.Collections.Generic;
-using System.Diagnostics;
 using System.IO;
-using System.Text;
-using System.Text.RegularExpressions;
+using System.Net;
+using System.Net.Sockets;
 using System.Threading;
-
 using v2rayN.Mode;
 using v2rayN.Protos.Statistics;
 
-using Grpc.Core;
-
 namespace v2rayN.Handler
 {
     class StatisticsHandler
@@ -63,19 +60,24 @@ public StatisticsHandler(Mode.Config config, Action<ulong, ulong, ulong, ulong,
                 Statistic.Add(statistic);
             }
 
-            loadFromFile();
+            LoadFromFile();
 
-            grpcInit();
+            GrpcInit();
 
-            workThread_ = new Thread(new ThreadStart(run));
+            workThread_ = new Thread(new ThreadStart(Run));
             workThread_.Start();
         }
 
-        private void grpcInit()
+        private void GrpcInit()
         {
-            channel_ = new Channel($"127.0.0.1:{Global.InboundAPIPort}", ChannelCredentials.Insecure);
-            channel_.ConnectAsync();
-            client_ = new StatsService.StatsServiceClient(channel_);
+            if (channel_ == null)
+            {
+                Global.statePort = GetFreePort();
+
+                channel_ = new Channel($"127.0.0.1:{Global.statePort}", ChannelCredentials.Insecure);
+                channel_.ConnectAsync();
+                client_ = new StatsService.StatsServiceClient(channel_);
+            }
         }
 
         public void Close()
@@ -92,7 +94,7 @@ public void Close()
             }
         }
 
-        public void run()
+        public void Run()
         {
             while (!exitFlag_)
             {
@@ -120,7 +122,7 @@ public void run()
                                  down = 0;
 
                             //TODO: parse output
-                            parseOutput(res.Stat, out up, out down);
+                            ParseOutput(res.Stat, out up, out down);
 
                             Up = up;
                             Down = down;
@@ -139,10 +141,9 @@ public void run()
                             if (UpdateUI)
                                 updateFunc_(TotalUp, TotalDown, Up, Down, Statistic);
                         }
-
-                        Thread.Sleep(config_.statisticsFreshRate);
-                        channel_.ConnectAsync();
                     }
+                    Thread.Sleep(config_.statisticsFreshRate);
+                    channel_.ConnectAsync();
                 }
                 catch (Exception ex)
                 {
@@ -151,7 +152,7 @@ public void run()
             }
         }
 
-        public void parseOutput(Google.Protobuf.Collections.RepeatedField<Stat> source, out ulong up, out ulong down)
+        public void ParseOutput(Google.Protobuf.Collections.RepeatedField<Stat> source, out ulong up, out ulong down)
         {
 
             up = 0; down = 0;
@@ -189,7 +190,7 @@ public void parseOutput(Google.Protobuf.Collections.RepeatedField<Stat> source,
             }
         }
 
-        public void saveToFile()
+        public void SaveToFile()
         {
             if (!Directory.Exists(logPath_))
             {
@@ -249,7 +250,7 @@ public void saveToFile()
             }
         }
 
-        public void loadFromFile()
+        public void LoadFromFile()
         {
             if (!Directory.Exists(logPath_)) return;
 
@@ -397,5 +398,25 @@ private void DeleteExpiredLog()
                 Utils.SaveLog(ex.Message, ex);
             }
         }
+
+        private int GetFreePort()
+        {
+            int defaultPort = 28123;
+            try
+            {
+                // TCP stack please do me a favor
+                TcpListener l = new TcpListener(IPAddress.Loopback, 0);
+                l.Start();
+                var port = ((IPEndPoint)l.LocalEndpoint).Port;
+                l.Stop();
+                return port;
+            }
+            catch (Exception ex)
+            {
+                // in case access denied
+                Utils.SaveLog(ex.Message, ex);
+                return defaultPort;
+            }
+        }
     }
 }
diff --git a/v2rayN/v2rayN/Handler/V2rayConfigHandler.cs b/v2rayN/v2rayN/Handler/V2rayConfigHandler.cs
index bf417ab0d0..7f8cc0c815 100644
--- a/v2rayN/v2rayN/Handler/V2rayConfigHandler.cs
+++ b/v2rayN/v2rayN/Handler/V2rayConfigHandler.cs
@@ -631,26 +631,28 @@ public static int statistic(Config config, ref V2rayConfig v2rayConfig)
                 v2rayConfig.stats = new Stats();
 
                 apiObj.tag = tag;
-                apiObj.services =  services.ToList();
+                apiObj.services = services.ToList();
                 v2rayConfig.api = apiObj;
 
                 policySystemSetting.statsInboundDownlink = true;
                 policySystemSetting.statsInboundUplink = true;
                 policyObj.system = policySystemSetting;
                 v2rayConfig.policy = policyObj;
-                if(!v2rayConfig.inbounds.Exists(item => { return item.tag == tag; }))
+
+                if (!v2rayConfig.inbounds.Exists(item => { return item.tag == tag; }))
                 {
                     var apiInbound = new Mode.Inbounds();
                     var apiInboundSettings = new Mode.Inboundsettings();
                     apiInbound.tag = tag;
                     apiInbound.listen = Global.Loopback;
-                    apiInbound.port = config.port();
+                    apiInbound.port = Global.statePort;
                     apiInbound.protocol = Global.InboundAPIProtocal;
                     apiInboundSettings.address = Global.Loopback;
                     apiInbound.settings = apiInboundSettings;
                     v2rayConfig.inbounds.Add(apiInbound);
                 }
-                if(!v2rayConfig.routing.rules.Exists(item => { return item.outboundTag == tag; }))
+
+                if (!v2rayConfig.routing.rules.Exists(item => { return item.outboundTag == tag; }))
                 {
                     var apiRoutingRule = new Mode.RulesItem();
                     apiRoutingRule.inboundTag = tag;
@@ -1153,14 +1155,14 @@ public static VmessItem ImportFromClipboardConfig(string clipboardData, out stri
                         vmessItem.network = Global.DefaultNetwork;
                         vmessItem.headerType = Global.None;
 
-                      
+
                         vmessItem.configVersion = Utils.ToInt(vmessQRCode.v);
                         vmessItem.remarks = Utils.ToString(vmessQRCode.ps);
                         vmessItem.address = Utils.ToString(vmessQRCode.add);
                         vmessItem.port = Utils.ToInt(vmessQRCode.port);
                         vmessItem.id = Utils.ToString(vmessQRCode.id);
                         vmessItem.alterId = Utils.ToInt(vmessQRCode.aid);
-                    
+
                         if (!Utils.IsNullOrEmpty(vmessQRCode.net))
                         {
                             vmessItem.network = vmessQRCode.net;
@@ -1169,7 +1171,7 @@ public static VmessItem ImportFromClipboardConfig(string clipboardData, out stri
                         {
                             vmessItem.headerType = vmessQRCode.type;
                         }
-                         
+
                         vmessItem.requestHost = Utils.ToString(vmessQRCode.host);
                         vmessItem.path = Utils.ToString(vmessQRCode.path);
                         vmessItem.streamSecurity = Utils.ToString(vmessQRCode.tls);
diff --git a/v2rayN/v2rayN/Mode/V2rayConfig.cs b/v2rayN/v2rayN/Mode/V2rayConfig.cs
index d969b539cc..3a25ac0d28 100644
--- a/v2rayN/v2rayN/Mode/V2rayConfig.cs
+++ b/v2rayN/v2rayN/Mode/V2rayConfig.cs
@@ -21,40 +21,14 @@ public class V2rayConfig
         /// </summary>
         public List<Outbounds> outbounds { get; set; }
 
-        /// 网速统计
-        /// 使用v2ray api功能
-        /// 
-        /// routing->rules 需要加上这一条
-        /// {
-        ///     "inboundTag": [
-        ///         "api"
-        ///     ],
-        ///     "outboundTag": "api",
-        ///     "type": "field"
-        /// }
-
         /// <summary>
         /// 统计需要， 空对象
         /// </summary>
         public Stats stats { get; set; }
-
-        /// <summary>
-        /// 需要tag和services
-        /// "api": {
-        ///     "tag": "api",
-        ///     "services": [
-        ///         "StatsService"
-        ///     ]
-        /// }
+       
         /// </summary>
         public API api { get; set; }
 
-        /// <summary>
-        /// policy 都设置为true；
-        /// "system": {
-        ///     "statsInboundUplink": true,
-        ///     "statsInboundDownlink": true
-        /// }
         /// </summary>
         public Policy policy;
 
diff --git a/v2rayN/v2rayN/Properties/AssemblyInfo.cs b/v2rayN/v2rayN/Properties/AssemblyInfo.cs
index 120670017d..e7cbee3a86 100644
--- a/v2rayN/v2rayN/Properties/AssemblyInfo.cs
+++ b/v2rayN/v2rayN/Properties/AssemblyInfo.cs
@@ -33,4 +33,4 @@
 // 方法是按如下所示使用“*”:
 //[assembly: AssemblyVersion("1.0.*")]
 //[assembly: AssemblyVersion("1.0.0")]
-[assembly: AssemblyFileVersion("2.37")]
+[assembly: AssemblyFileVersion("2.38")]
diff --git a/v2rayN/v2rayN/Sample/SampleClientConfig.txt b/v2rayN/v2rayN/Sample/SampleClientConfig.txt
index 2b134ca334..11572d8a4d 100644
--- a/v2rayN/v2rayN/Sample/SampleClientConfig.txt
+++ b/v2rayN/v2rayN/Sample/SampleClientConfig.txt
@@ -1,17 +1,4 @@
-{
-	"stats": {},
-	"api": {
-		"tag": "api",
-		"services": [
-			"StatsService"
-		]
-	},
-	"policy": {
-		"system": {
-			"statsInboundUplink": true,
-			"statsInboundDownlink": true
-		}
-	},
+{	 
 	"log": {
 		"access": "",
 		"error": "",
@@ -39,16 +26,7 @@
 					"tls"
 				]
 			}
-		},
-		{
-            "listen": "127.0.0.1",
-            "port": 10805,
-            "protocol": "dokodemo-door",
-            "settings": {
-                "address": "127.0.0.1"
-            },
-            "tag": "api"
-        }
+		}
 	],
 	"outbounds": [{
 			"tag": "proxy",