diff --git a/host/src/capture_panel.cpp b/host/src/capture_panel.cpp
index 2615ac0..62f73bb 100644
--- a/host/src/capture_panel.cpp
+++ b/host/src/capture_panel.cpp
@@ -57,6 +57,15 @@ void plot_multiseries(const char* id, const GraphSeries* series, int n_series, f
 }
 } // namespace
 
+bool CapturePanel::frame_sync_active() const
+{
+	// Only sync to the hook's frames while the target is actually alive and producing
+	// them. A terminated or hung game stops bumping the generation, so syncing would make
+	// every iteration wait out the timeout in wait_for_hooked_frame -- fall back to vsync.
+	const bool hook_alive = injection_ != nullptr && injection_->target_state() == TargetState::Alive;
+	return frame_sync_ && enabled_ && source_ == Source_Hooked && hook_alive;
+}
+
 bool CapturePanel::init(ID3D11Device* device)
 {
 	device_ = device;
diff --git a/host/src/capture_panel.hpp b/host/src/capture_panel.hpp
index d0f37f5..03c4591 100644
--- a/host/src/capture_panel.hpp
+++ b/host/src/capture_panel.hpp
@@ -58,13 +58,13 @@ public:
 		return source_ == Source_Hooked;
 	}
 
-	// True when the operator asked to pace the tool's flip to the game's published
-	// frames (only meaningful with the Hooked source while mirroring). The main loop
-	// reads this to wait for a new hook frame and present without vsync.
-	[[nodiscard]] bool frame_sync_active() const
-	{
-		return frame_sync_ && enabled_ && source_ == Source_Hooked;
-	}
+	// True when the operator asked to pace the tool's flip to the game's published frames
+	// (only meaningful with the Hooked source while mirroring) AND the target is alive and
+	// still producing them. The main loop reads this to wait for a new hook frame and
+	// present without vsync; gating on liveness stops a terminated/hung game from making
+	// every frame wait out the sync timeout (~5 FPS sluggish overlay). Defined in the .cpp
+	// since it needs the InjectionPanel definition for target liveness.
+	[[nodiscard]] bool frame_sync_active() const;
 
 private:
 	enum Source : int