diff --git a/hook/src/present_hook.cpp b/hook/src/present_hook.cpp
index d4bbc75..02da887 100644
--- a/hook/src/present_hook.cpp
+++ b/hook/src/present_hook.cpp
@@ -9,6 +9,7 @@
 #include <d3d11on12.h>
 #include <d3d12.h>
 #include <dxgi1_2.h>
+#include <dxgi1_4.h>
 
 #include <safetyhook.hpp>
 
@@ -247,8 +248,25 @@ bool ensure_on12_locked(ID3D12Device* dev)
 // via the On12 bridge and CopyResource it into the shared texture.
 void capture_backbuffer_d3d12(IDXGISwapChain* sc)
 {
+	// CRITICAL: D3D12 rotates back buffers explicitly -- the game rendered into the
+	// buffer at GetCurrentBackBufferIndex(), and that index advances every Present.
+	// (Unlike D3D11 flip-model, where DXGI keeps GetBuffer(0) pointing at the live
+	// back buffer.) Grabbing buffer 0 unconditionally copies a stale buffer on N-1 of
+	// every N frames, so the mirror silently runs at refresh/N with duplicate frames
+	// in between -- even though the Present counter, published FPS, generation bump,
+	// and latency all read full rate (they count Presents, not unique content). We're
+	// called before the trampoline Present, so the current index is the just-rendered
+	// buffer. Query IDXGISwapChain3 for it; fall back to 0 only if unavailable.
+	UINT bb_index = 0;
+	IDXGISwapChain3* sc3 = nullptr;
+	if (SUCCEEDED(sc->QueryInterface(__uuidof(IDXGISwapChain3), reinterpret_cast<void**>(&sc3))) && sc3 != nullptr)
+	{
+		bb_index = sc3->GetCurrentBackBufferIndex();
+		sc3->Release();
+	}
+
 	ID3D12Resource* bb = nullptr;
-	if (FAILED(sc->GetBuffer(0, __uuidof(ID3D12Resource), reinterpret_cast<void**>(&bb))) || bb == nullptr)
+	if (FAILED(sc->GetBuffer(bb_index, __uuidof(ID3D12Resource), reinterpret_cast<void**>(&bb))) || bb == nullptr)
 	{
 		if (!g_unsupported_logged)
 		{