diff --git a/Outputs/CRT/CRT.cpp b/Outputs/CRT/CRT.cpp
index 55157b83c..7e1199b7a 100644
--- a/Outputs/CRT/CRT.cpp
+++ b/Outputs/CRT/CRT.cpp
@@ -281,8 +281,11 @@ void CRT::output_scan(const Scan *const scan)
 	const bool is_leading_edge = (!_is_receiving_sync && this_is_sync);
 	_is_receiving_sync = this_is_sync;
 
-	const bool hsync_requested = is_leading_edge;
-//	const bool hsync_requested = is_trailing_edge && (_sync_period < (_horizontal_flywheel->get_scan_period() >> 2));
+	// This introduces a blackout period close to the expected vertical sync point in which horizontal syncs are not
+	// recognised, effectively causing the horizontal flywheel to freewheel during that period. This attempts to seek
+	// the problem that vertical sync otherwise often starts halfway through a scanline, which confuses the horizontal
+	// flywheel. I'm currently unclear whether this is an accurate solution to this problem.
+	const bool hsync_requested = is_leading_edge && !_vertical_flywheel->is_near_expected_sync();
 	const bool vsync_requested = is_trailing_edge && (_sync_capacitor_charge_level >= _sync_capacitor_charge_threshold);
 
 	// simplified colour burst logic: if it's within the back porch we'll take it
diff --git a/Outputs/CRT/Internals/Flywheel.hpp b/Outputs/CRT/Internals/Flywheel.hpp
index e10d621fd..c3a00a3aa 100644
--- a/Outputs/CRT/Internals/Flywheel.hpp
+++ b/Outputs/CRT/Internals/Flywheel.hpp
@@ -9,6 +9,8 @@
 #ifndef Flywheel_hpp
 #define Flywheel_hpp
 
+#include <stdlib.h>
+
 namespace Outputs {
 namespace CRT {
 
@@ -187,6 +189,14 @@ struct Flywheel
 		return result;
 	}
 
+	/*!
+		@returns `true` if a sync is expected soon or the time at which it was expected was recent.
+	*/
+	inline bool is_near_expected_sync()
+	{
+		return abs((int)_counter - (int)_expected_next_sync) < (int)_standard_period / 50;
+	}
+
 	private:
 		unsigned int _standard_period;			// the normal length of time between syncs
 		const unsigned int _retrace_time;		// a constant indicating the amount of time it takes to perform a retrace