diff --git a/Assets/uDesktopDuplication/Plugins/x86/uDesktopDuplication.dll b/Assets/uDesktopDuplication/Plugins/x86/uDesktopDuplication.dll
index 3e79509..bffcb10 100644
Binary files a/Assets/uDesktopDuplication/Plugins/x86/uDesktopDuplication.dll and b/Assets/uDesktopDuplication/Plugins/x86/uDesktopDuplication.dll differ
diff --git a/Assets/uDesktopDuplication/Plugins/x86_64/uDesktopDuplication.dll b/Assets/uDesktopDuplication/Plugins/x86_64/uDesktopDuplication.dll
index 7b91e1b..98e89cb 100644
Binary files a/Assets/uDesktopDuplication/Plugins/x86_64/uDesktopDuplication.dll and b/Assets/uDesktopDuplication/Plugins/x86_64/uDesktopDuplication.dll differ
diff --git a/Plugins/uDesktopDuplication/uDesktopDuplication/Duplicator.cpp b/Plugins/uDesktopDuplication/uDesktopDuplication/Duplicator.cpp
index 85bec14..a04a2d4 100644
--- a/Plugins/uDesktopDuplication/uDesktopDuplication/Duplicator.cpp
+++ b/Plugins/uDesktopDuplication/uDesktopDuplication/Duplicator.cpp
@@ -214,9 +214,11 @@ bool Duplicator::Duplicate()
 {
     if (!dupl_ || !device_) return false;
 
+    const UINT timeout = 16;
+
     ComPtr<IDXGIResource> resource;
     DXGI_OUTDUPL_FRAME_INFO frameInfo;
-    const auto hr = dupl_->AcquireNextFrame(INFINITE, &frameInfo, &resource);
+    const auto hr = dupl_->AcquireNextFrame(timeout, &frameInfo, &resource);
 
     if (FAILED(hr)) 
     {
@@ -228,32 +230,31 @@ bool Duplicator::Duplicate()
                 // it is necessary to re-initialize monitors.
                 Debug::Log("Duplicator::Duplicate() => DXGI_ERROR_ACCESS_LOST.");
                 state_ = State::AccessLost;
-                break;
+                return false;
             }
             case DXGI_ERROR_WAIT_TIMEOUT:
             {
                 // This often occurs when timeout value is small and it is not problem. 
                 // Debug::Log("Duplicator::Duplicate() => DXGI_ERROR_WAIT_TIMEOUT.");
-                break;
+                return true;
             }
             case DXGI_ERROR_INVALID_CALL:
             {
                 Debug::Error("Duplicator::Duplicate() => DXGI_ERROR_INVALID_CALL.");
-                break;
+                return false;
             }
             case E_INVALIDARG:
             {
                 Debug::Error("Duplicator::Duplicate() => E_INVALIDARG.");
-                break;
+                return false;
             }
             default:
             {
                 state_ = State::Unknown;
                 Debug::Error("Duplicator::Duplicate() => Unknown Error.");
-                break;
+                return false;
             }
         }
-        return false;
     }
 
     ScopedReleaser releaser([this] 
diff --git a/Plugins/uDesktopDuplication/uDesktopDuplication/Duplicator.h b/Plugins/uDesktopDuplication/uDesktopDuplication/Duplicator.h
index a048377..d94aad7 100644
--- a/Plugins/uDesktopDuplication/uDesktopDuplication/Duplicator.h
+++ b/Plugins/uDesktopDuplication/uDesktopDuplication/Duplicator.h
@@ -3,6 +3,7 @@
 #include <d3d11.h>
 #include <dxgi1_2.h>
 #include <memory>
+#include <atomic>
 #include <thread>
 #include <mutex>
 #include <wrl/client.h>
@@ -73,7 +74,7 @@ private:
     void UpdateDirtyRects();
 
     Monitor* monitor_ = nullptr;
-    State state_ = State::Ready;
+    std::atomic<State> state_ = State::Ready;
 
     std::shared_ptr<class IsolatedD3D11Device> device_;
     Microsoft::WRL::ComPtr<IDXGIOutputDuplication> dupl_;