diff --git a/include/rtmp_manager.hpp b/include/rtmp_manager.hpp
index a894508..ebc7a7e 100644
--- a/include/rtmp_manager.hpp
+++ b/include/rtmp_manager.hpp
@@ -63,9 +63,11 @@ class RTMPManager
     struct StreamContext
     {
         std::atomic<bool> running{false};
+        std::atomic<bool> start_result_set{false};  // 新增：保证 promise 只 set 一次
         std::thread thread;
         std::promise<StreamResultInfo> start_result;
         StreamStatus status;
+
         StreamContext() = default;
         StreamContext(const StreamContext &) = delete;
         StreamContext &operator=(const StreamContext &) = delete;
diff --git a/src/rtmp_manager.cpp b/src/rtmp_manager.cpp
index eb7e0c6..57f5dfd 100644
--- a/src/rtmp_manager.cpp
+++ b/src/rtmp_manager.cpp
@@ -103,10 +103,13 @@ RTMPManager::StreamResultInfo RTMPManager::start_camera(const Camera &cam, Strea
         streams[key] = std::move(ctx);
     }
 
+    // future 用于等待 first frame 或初始化结果
     std::future<StreamResultInfo> fut = ctx_ptr->start_result.get_future();
 
+    // 启动线程
     ctx_ptr->thread = std::thread([cam, type, ctx_ptr]() { RTMPManager::stream_loop(cam, type, ctx_ptr); });
 
+    // 等待初始化完成（收到第一帧或错误）
     if (fut.wait_for(std::chrono::seconds(10)) == std::future_status::ready)
     {
         res = fut.get();
@@ -115,6 +118,10 @@ RTMPManager::StreamResultInfo RTMPManager::start_camera(const Camera &cam, Strea
     {
         res.result = 1;
         res.reason = "Start timeout";
+
+        // 超时后安全地停止线程
+        ctx_ptr->running.store(false);
+        if (ctx_ptr->thread.joinable()) ctx_ptr->thread.join();
     }
 
     return res;
@@ -129,6 +136,7 @@ RTMPManager::StreamResultInfo RTMPManager::stop_camera(const std::string &cam_na
 
     std::unique_ptr<StreamContext> ctx;
     std::string key = make_stream_key(cam_name, type);
+
     {
         std::lock_guard<std::mutex> lock(streams_mutex);
         auto it = streams.find(key);
@@ -136,15 +144,24 @@ RTMPManager::StreamResultInfo RTMPManager::stop_camera(const std::string &cam_na
         {
             res.result = 0;
             res.reason = "Not streaming";
+            LOG_INFO("[RTMP] stop_camera: " + key + " is not streaming");
             return res;
         }
 
+        // 设置停止标志，stream_loop 会退出
         it->second->running.store(false);
+
+        // 转移所有权，map 里移除
         ctx = std::move(it->second);
         streams.erase(it);
     }
 
-    if (ctx->thread.joinable()) ctx->thread.join();
+    // 等待线程退出
+    if (ctx && ctx->thread.joinable())
+    {
+        ctx->thread.join();
+        LOG_INFO("[RTMP] stop_camera: " + key + " stopped");
+    }
 
     res.result = 0;
     res.reason = "Stopped manually";
@@ -167,7 +184,7 @@ void RTMPManager::stream_loop(Camera cam, StreamType type, StreamContext *ctx)
     {
         res.result = 1;
         res.reason = "Failed to create pipeline";
-        ctx->start_result.set_value(res);
+        if (ctx->start_result_set.compare_exchange_strong(expected, true)) ctx->start_result.set_value(res);
         return;
     }
 
@@ -198,7 +215,8 @@ void RTMPManager::stream_loop(Camera cam, StreamType type, StreamContext *ctx)
             {
                 res.result = 1;
                 res.reason = "No frames received within timeout";
-                ctx->start_result.set_value(res);
+                bool expected = false;
+                if (ctx->start_result_set.compare_exchange_strong(expected, true)) ctx->start_result.set_value(res);
                 break;
             }
         }
@@ -215,7 +233,8 @@ void RTMPManager::stream_loop(Camera cam, StreamType type, StreamContext *ctx)
                 std::string err_msg = err ? err->message : "Unknown GStreamer error";
                 res.result = 1;
                 res.reason = "Pipeline error: " + err_msg;
-                ctx->start_result.set_value(res);
+                bool expected = false;
+                if (ctx->start_result_set.compare_exchange_strong(expected, true)) ctx->start_result.set_value(res);
                 if (err) g_error_free(err);
                 if (debug) g_free(debug);
                 break;
@@ -223,7 +242,10 @@ void RTMPManager::stream_loop(Camera cam, StreamType type, StreamContext *ctx)
             case GST_MESSAGE_EOS:
                 res.result = 1;
                 res.reason = "EOS received";
-                ctx->start_result.set_value(res);
+                {
+                    bool expected = false;
+                    if (ctx->start_result_set.compare_exchange_strong(expected, true)) ctx->start_result.set_value(res);
+                }
                 break;
             case GST_MESSAGE_STATE_CHANGED:
                 // pipeline 播放状态变化，不算成功
@@ -234,7 +256,8 @@ void RTMPManager::stream_loop(Camera cam, StreamType type, StreamContext *ctx)
                     first_frame_received = true;
                     res.result = 0;
                     res.reason = "First frame received, started OK";
-                    ctx->start_result.set_value(res);
+                    bool expected = false;
+                    if (ctx->start_result_set.compare_exchange_strong(expected, true)) ctx->start_result.set_value(res);
                 }
                 break;
             default:
@@ -275,15 +298,29 @@ bool RTMPManager::is_any_streaming()
 void RTMPManager::stop_all()
 {
     std::vector<std::unique_ptr<StreamContext>> ctxs;
+
     {
         std::lock_guard<std::mutex> lock(streams_mutex);
-        for (auto &kv : streams) kv.second->running.store(false);
-        for (auto &kv : streams) ctxs.push_back(std::move(kv.second));
+
+        // 设置所有流停止标志，并收集上下文
+        for (auto &kv : streams)
+        {
+            kv.second->running.store(false);
+            ctxs.push_back(std::move(kv.second));
+            LOG_INFO("[RTMP] stop_all: stopping stream " + kv.first);
+        }
+
         streams.clear();
     }
 
+    // 等待所有线程退出
     for (auto &ctx : ctxs)
-        if (ctx->thread.joinable()) ctx->thread.join();
+    {
+        if (ctx && ctx->thread.joinable())
+        {
+            ctx->thread.join();
+        }
+    }
 
     LOG_INFO("[RTMP] stop_all completed.");
 }