diff --git a/src/main.cpp b/src/main.cpp
index a1fcece..c1df2e0 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -9,15 +9,34 @@
 
 std::atomic<bool> g_running(true);
 
-void signalHandler(int)
+void signalHandler(int signum)
 {
+    static bool already_called = false;
+    if (already_called)
+        return;
+    already_called = true;
+
+    LOG_INFO("[MAIN] Received signal " + std::to_string(signum) + ", shutting down...");
     g_running = false;
     RTSPManager::stop(); // 停止 RTSP loop
+
+    // 设置超时，防止无限等待
+    std::this_thread::sleep_for(std::chrono::milliseconds(500));
+
+    // 强制退出如果仍然卡住
+    if (signum == SIGINT)
+    {
+        exit(1);
+    }
 }
 
 int main()
 {
-    signal(SIGINT, signalHandler);
+    struct sigaction sigIntHandler;
+    sigIntHandler.sa_handler = signalHandler;
+    sigemptyset(&sigIntHandler.sa_mask);
+    sigIntHandler.sa_flags = 0;
+    sigaction(SIGINT, &sigIntHandler, NULL);
     signal(SIGPIPE, SIG_IGN);
 
     // 初始化日志文件
@@ -45,11 +64,19 @@ int main()
     while (g_running)
         std::this_thread::sleep_for(std::chrono::milliseconds(200));
 
-    // 等待退出信号
+    // 在main函数等待线程结束处添加日志
     if (rtsp_thread.joinable())
+    {
+        LOG_INFO("[MAIN] Waiting for RTSP thread to finish...");
         rtsp_thread.join();
+        LOG_INFO("[MAIN] RTSP thread finished");
+    }
     if (mqtt_thread.joinable())
+    {
+        LOG_INFO("[MAIN] Waiting for MQTT thread to finish...");
         mqtt_thread.join();
+        LOG_INFO("[MAIN] MQTT thread finished");
+    }
 
     LOG_INFO("[MAIN] Program exited cleanly.");
     return 0;
diff --git a/src/mqtt_client.cpp b/src/mqtt_client.cpp
index d8f3337..c6a8812 100644
--- a/src/mqtt_client.cpp
+++ b/src/mqtt_client.cpp
@@ -38,9 +38,6 @@ void MQTTClient::connect()
                             .finalize();
 
         client_->connect(connOpts)->wait(); // 阻塞等待连接
-        connected_ = true;
-        if (on_connect_)
-            on_connect_();
     }
     catch (const mqtt::exception &e)
     {
diff --git a/src/mqtt_client_wrapper.cpp b/src/mqtt_client_wrapper.cpp
index f4baddd..85ed282 100644
--- a/src/mqtt_client_wrapper.cpp
+++ b/src/mqtt_client_wrapper.cpp
@@ -219,8 +219,12 @@ void mqtt_client_thread_func()
             catch (...)
             {
             }
-            if (!mqtt_client->isConnected())
-                std::this_thread::sleep_for(std::chrono::seconds(2));
+
+            // 更频繁地检查退出标志
+            for (int i = 0; i < 10 && g_running && !mqtt_client->isConnected(); i++)
+            {
+                std::this_thread::sleep_for(std::chrono::milliseconds(200));
+            }
         }
 
         while (g_running && mqtt_client->isConnected())
@@ -233,12 +237,22 @@ void mqtt_client_thread_func()
             {
                 LOG_ERROR("[MQTT] Heartbeat error: " + std::string(e.what()));
             }
-            std::this_thread::sleep_for(heartbeat_interval);
+            // 将长睡眠拆分为多个短睡眠，以便更频繁检查退出标志
+            auto sleep_time = heartbeat_interval;
+            while (sleep_time.count() > 0 && g_running && mqtt_client->isConnected())
+            {
+                auto chunk = std::min(sleep_time, std::chrono::milliseconds(200));
+                std::this_thread::sleep_for(chunk);
+                sleep_time -= chunk;
+            }
         }
 
         // 需要重启或退出
-        mqtt_client->disconnect();
-        mqtt_client.reset();
+        if (mqtt_client)
+        {
+            mqtt_client->disconnect();
+            mqtt_client.reset();
+        }
         mqtt_restart_required = false;
     }
     LOG_INFO("[MQTT] Client thread exiting.");