diff --git a/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/NESControllers.cs b/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/NESControllers.cs
index 3329d95c01..d0782c489f 100644
--- a/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/NESControllers.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/NESControllers.cs
@@ -97,12 +97,12 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
 
 		public byte ReadA(IController c)
 		{
-			return (byte)(Left.Read(LeftU.UnMerge(c)) & 0x13);
+			return (byte)(Left.Read(LeftU.UnMerge(c)) & 0x19);
 		}
 
 		public byte ReadB(IController c)
 		{
-			return (byte)(Right.Read(RightU.UnMerge(c)) & 0x13);
+			return (byte)(Right.Read(RightU.UnMerge(c)) & 0x19);
 		}
 
 		public ControllerDefinition GetDefinition()