fix: reload audio output on Windows wake from sleep

windows/runner/mpv/mpv_core.cpp

@@ -147,6 +147,11 @@ std::optional<HRESULT> MpvCore::WindowProc(HWND hwnd, UINT message,
           ::RedrawWindow(flutter_window_, nullptr, nullptr,
                          RDW_INVALIDATE | RDW_UPDATENOW | RDW_ALLCHILDREN);
         }
+      } else if (wparam == kPowerResumeTimerId) {
+        ::KillTimer(flutter_window_, kPowerResumeTimerId);
+        if (power_resume_cb_) {
+          power_resume_cb_();
+        }
       }
       break;
     }
@@ -170,6 +175,14 @@ std::optional<HRESULT> MpvCore::WindowProc(HWND hwnd, UINT message,
       }
       break;
     }
+    case WM_POWERBROADCAST: {
+      if (wparam == PBT_APMRESUMEAUTOMATIC && power_resume_cb_) {
+        // Delay audio reload to let WASAPI fully reinitialize after wake.
+        ::KillTimer(flutter_window_, kPowerResumeTimerId);
+        ::SetTimer(flutter_window_, kPowerResumeTimerId, kPowerResumeAudioDelay, nullptr);
+      }
+      break;
+    }
     case WM_CLOSE: {
       ::SendMessage(container_, WM_CLOSE, 0, 0);
       for (const auto& [mpv_view, rect] : mpv_views_) {
@@ -202,6 +215,10 @@ RECT MpvCore::GetGlobalRect(int32_t left, int32_t top, int32_t right,
   return rect;
 }
 
+void MpvCore::SetPowerResumeCallback(PowerResumeCallback callback) {
+  power_resume_cb_ = std::move(callback);
+}
+
 std::unique_ptr<MpvCore> MpvCore::instance_ = nullptr;
 
 }  // namespace mpv

windows/runner/mpv/mpv_core.h

@@ -4,6 +4,7 @@
 #include <Windows.h>
 
 #include <cmath>
+#include <functional>
 #include <map>
 #include <memory>
 #include <optional>
@@ -15,7 +16,9 @@ namespace mpv {
 class MpvCore {
  public:
   static constexpr auto kPositionAndShowDelay = 300;
+  static constexpr auto kPowerResumeAudioDelay = 500;
   static constexpr UINT_PTR kCompositionRestoreTimerId = 1001;
+  static constexpr UINT_PTR kPowerResumeTimerId = 1002;
 
   static MpvCore* GetInstance();
   static void SetInstance(std::unique_ptr<MpvCore> instance);
@@ -42,6 +45,10 @@ class MpvCore {
   std::optional<HRESULT> WindowProc(HWND hwnd, UINT message, WPARAM wparam,
                                     LPARAM lparam);
 
+  // Callback invoked when Windows resumes from sleep/hibernate.
+  using PowerResumeCallback = std::function<void()>;
+  void SetPowerResumeCallback(PowerResumeCallback callback);
+
  private:
   RECT GetGlobalRect(int32_t left, int32_t top, int32_t right, int32_t bottom);
 
@@ -53,6 +60,7 @@ class MpvCore {
   bool was_window_hidden_due_to_minimize_ = false;
   bool visible_ = true;
   bool composition_enabled_ = false;
+  PowerResumeCallback power_resume_cb_;
 
   static std::unique_ptr<MpvCore> instance_;
 };

windows/runner/mpv/mpv_plugin.cpp

@@ -121,6 +121,16 @@ void MpvPlayerPlugin::HandleMethodCall(
       RECT rect = {0, 0, 100, 100};
       MpvCore::GetInstance()->CreateMpvView(player_->GetHwnd(), rect, 1.0);
 
+      // Reload audio output on wake from sleep to recover stale WASAPI sessions.
+      MpvCore::GetInstance()->SetPowerResumeCallback([this]() {
+        if (player_ && player_->IsInitialized()) {
+          auto device = player_->GetProperty("audio-device");
+          if (!device.empty()) {
+            player_->SetProperty("audio-device", device);
+          }
+        }
+      });
+
       // Start hidden.
       MpvCore::GetInstance()->SetVisible(false);
       result->Success(flutter::EncodableValue(true));