diff --git a/BizHawk.Emulation.Common/Interfaces/IInputPollable.cs b/BizHawk.Emulation.Common/Interfaces/IInputPollable.cs
index 54a3ef5f50..fdb9259a8e 100644
--- a/BizHawk.Emulation.Common/Interfaces/IInputPollable.cs
+++ b/BizHawk.Emulation.Common/Interfaces/IInputPollable.cs
@@ -11,7 +11,7 @@
 		/// If the current frame is a lag frame.
 		/// All cores should define it the same, a lag frame is a frame in which input was not polled.
 		/// </summary>
-		bool IsLagFrame { get; }
+		bool IsLagFrame { get; set; }
 
 		IInputCallbackSystem InputCallbacks { get; }
 	}
diff --git a/BizHawk.Emulation.Cores/Calculator/TI83.IInputPollable.cs b/BizHawk.Emulation.Cores/Calculator/TI83.IInputPollable.cs
index 22927c62ee..b4eb0fa967 100644
--- a/BizHawk.Emulation.Cores/Calculator/TI83.IInputPollable.cs
+++ b/BizHawk.Emulation.Cores/Calculator/TI83.IInputPollable.cs
@@ -19,6 +19,7 @@ namespace BizHawk.Emulation.Cores.Calculators
 		public bool IsLagFrame
 		{
 			get { return _isLag; }
+            set { _isLag = value; }
 		}
 	}
 }
diff --git a/BizHawk.Emulation.Cores/Computers/AppleII/AppleII.IInputPollable.cs b/BizHawk.Emulation.Cores/Computers/AppleII/AppleII.IInputPollable.cs
index 26419f41e5..a595a2b73b 100644
--- a/BizHawk.Emulation.Cores/Computers/AppleII/AppleII.IInputPollable.cs
+++ b/BizHawk.Emulation.Cores/Computers/AppleII/AppleII.IInputPollable.cs
@@ -9,7 +9,7 @@ namespace BizHawk.Emulation.Cores.Computers.AppleII
 		public bool IsLagFrame
 		{
 			get { return _machine.Lagged; }
-			private set { _machine.Lagged = value; }
+			set { _machine.Lagged = value; }
 		}
 
 		public IInputCallbackSystem InputCallbacks { get; private set; }
diff --git a/BizHawk.Emulation.Cores/Computers/Commodore64/C64.IInputPollable.cs b/BizHawk.Emulation.Cores/Computers/Commodore64/C64.IInputPollable.cs
index b0aef31cbd..212b0e2678 100644
--- a/BizHawk.Emulation.Cores/Computers/Commodore64/C64.IInputPollable.cs
+++ b/BizHawk.Emulation.Cores/Computers/Commodore64/C64.IInputPollable.cs
@@ -7,6 +7,7 @@ namespace BizHawk.Emulation.Cores.Computers.Commodore64
 		public bool IsLagFrame
 		{
 			get { return _islag; }
+            set { _islag = value; }
 		}
 
 		public int LagCount
diff --git a/BizHawk.Emulation.Cores/Consoles/Atari/2600/Atari2600.IInputPollable.cs b/BizHawk.Emulation.Cores/Consoles/Atari/2600/Atari2600.IInputPollable.cs
index efe6e472c9..05f5d69a8e 100644
--- a/BizHawk.Emulation.Cores/Consoles/Atari/2600/Atari2600.IInputPollable.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Atari/2600/Atari2600.IInputPollable.cs
@@ -13,6 +13,7 @@ namespace BizHawk.Emulation.Cores.Atari.Atari2600
 		public bool IsLagFrame
 		{
 			get { return _islag; }
+            set { _islag = value; }
 		}
 
 		public IInputCallbackSystem InputCallbacks { get; private set; }
diff --git a/BizHawk.Emulation.Cores/Consoles/Atari/7800/Atari7800.IInputPollable.cs b/BizHawk.Emulation.Cores/Consoles/Atari/7800/Atari7800.IInputPollable.cs
index 74937501de..0efb7e7393 100644
--- a/BizHawk.Emulation.Cores/Consoles/Atari/7800/Atari7800.IInputPollable.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Atari/7800/Atari7800.IInputPollable.cs
@@ -13,6 +13,7 @@ namespace BizHawk.Emulation.Cores.Atari.Atari7800
 		public bool IsLagFrame
 		{
 			get { return _islag; }
+            set { _islag = value; }
 		}
 
 		public IInputCallbackSystem InputCallbacks { get; private set; }
diff --git a/BizHawk.Emulation.Cores/Consoles/Atari/lynx/Lynx.IInputPollable.cs b/BizHawk.Emulation.Cores/Consoles/Atari/lynx/Lynx.IInputPollable.cs
index 9ba1ba6b32..334b78474d 100644
--- a/BizHawk.Emulation.Cores/Consoles/Atari/lynx/Lynx.IInputPollable.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Atari/lynx/Lynx.IInputPollable.cs
@@ -10,7 +10,7 @@ namespace BizHawk.Emulation.Cores.Atari.Lynx
 	{
 		public int LagCount { get; set; }
 
-		public bool IsLagFrame { get; private set; }
+		public bool IsLagFrame { get; set; }
 
 		// TODO
 		public IInputCallbackSystem InputCallbacks
diff --git a/BizHawk.Emulation.Cores/Consoles/Coleco/ColecoVision.IInputPollable.cs b/BizHawk.Emulation.Cores/Consoles/Coleco/ColecoVision.IInputPollable.cs
index bfac04bd55..63853300ab 100644
--- a/BizHawk.Emulation.Cores/Consoles/Coleco/ColecoVision.IInputPollable.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Coleco/ColecoVision.IInputPollable.cs
@@ -14,6 +14,7 @@ namespace BizHawk.Emulation.Cores.ColecoVision
 		public bool IsLagFrame
 		{
 			get { return _isLag; }
+            set { _isLag = value; }
 		}
 
 		public IInputCallbackSystem InputCallbacks
diff --git a/BizHawk.Emulation.Cores/Consoles/Nintendo/GBA/MGBAHawk.cs b/BizHawk.Emulation.Cores/Consoles/Nintendo/GBA/MGBAHawk.cs
index cec1c68c4e..b2d06b0e42 100644
--- a/BizHawk.Emulation.Cores/Consoles/Nintendo/GBA/MGBAHawk.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Nintendo/GBA/MGBAHawk.cs
@@ -371,7 +371,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBA
 		}
 
 		public int LagCount { get; set; }
-		public bool IsLagFrame { get; private set; }
+		public bool IsLagFrame { get; set; }
 
 		[FeatureNotImplemented]
 		public IInputCallbackSystem InputCallbacks
diff --git a/BizHawk.Emulation.Cores/Consoles/Nintendo/GBA/Meteor.cs b/BizHawk.Emulation.Cores/Consoles/Nintendo/GBA/Meteor.cs
index 965192275e..3e918a1258 100644
--- a/BizHawk.Emulation.Cores/Consoles/Nintendo/GBA/Meteor.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Nintendo/GBA/Meteor.cs
@@ -102,7 +102,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBA
 
 		public int Frame { get; private set; }
 		public int LagCount { get; set; }
-		public bool IsLagFrame { get; private set; }
+		public bool IsLagFrame { get; set; }
 
 		private readonly InputCallbackSystem _inputCallbacks = new InputCallbackSystem();
 
diff --git a/BizHawk.Emulation.Cores/Consoles/Nintendo/GBA/VBANext.cs b/BizHawk.Emulation.Cores/Consoles/Nintendo/GBA/VBANext.cs
index f529b4ffbc..3678b24584 100644
--- a/BizHawk.Emulation.Cores/Consoles/Nintendo/GBA/VBANext.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Nintendo/GBA/VBANext.cs
@@ -116,7 +116,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBA
 
 		public int Frame { get; private set; }
 		public int LagCount { get; set; }
-		public bool IsLagFrame { get; private set; }
+		public bool IsLagFrame { get; set; }
 
 		private ITraceable Tracer { get; set; }
 
diff --git a/BizHawk.Emulation.Cores/Consoles/Nintendo/Gameboy/Gambatte.cs b/BizHawk.Emulation.Cores/Consoles/Nintendo/Gameboy/Gambatte.cs
index b8270fe39e..428b6a7894 100644
--- a/BizHawk.Emulation.Cores/Consoles/Nintendo/Gameboy/Gambatte.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Nintendo/Gameboy/Gambatte.cs
@@ -196,7 +196,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.Gameboy
 
         public int Frame { get; set; }
         public int LagCount { get; set; }
-        public bool IsLagFrame { get; private set; }
+        public bool IsLagFrame { get; set; }
 
         // all cycle counts are relative to a 2*1024*1024 mhz refclock
 
diff --git a/BizHawk.Emulation.Cores/Consoles/Nintendo/Gameboy/GambatteLink.IInputPollable.cs b/BizHawk.Emulation.Cores/Consoles/Nintendo/Gameboy/GambatteLink.IInputPollable.cs
index efddc620da..1148b51f94 100644
--- a/BizHawk.Emulation.Cores/Consoles/Nintendo/Gameboy/GambatteLink.IInputPollable.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Nintendo/Gameboy/GambatteLink.IInputPollable.cs
@@ -7,7 +7,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.Gameboy
 	{
 		public int LagCount { get; set; }
 
-		public bool IsLagFrame { get; private set; }
+		public bool IsLagFrame { get; set; }
 
 		public IInputCallbackSystem InputCallbacks
 		{
diff --git a/BizHawk.Emulation.Cores/Consoles/Nintendo/N64/N64.IInputPollable.cs b/BizHawk.Emulation.Cores/Consoles/Nintendo/N64/N64.IInputPollable.cs
index 14103da9d6..31d7b96745 100644
--- a/BizHawk.Emulation.Cores/Consoles/Nintendo/N64/N64.IInputPollable.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Nintendo/N64/N64.IInputPollable.cs
@@ -19,7 +19,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.N64
 				return !_inputProvider.LastFrameInputPolled;
 			}
 
-			internal set
+			set
 			{
 				if (_settings.UseMupenStyleLag)
 				{
diff --git a/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/NES.IInputPollable.cs b/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/NES.IInputPollable.cs
index 8438b25012..1d6212f445 100644
--- a/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/NES.IInputPollable.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Nintendo/NES/NES.IInputPollable.cs
@@ -13,6 +13,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
 		public bool IsLagFrame
 		{
 			get { return islag; }
+            set { islag = value; }
 		}
 
 		public IInputCallbackSystem InputCallbacks
diff --git a/BizHawk.Emulation.Cores/Consoles/Nintendo/QuickNES/QuickNES.IInputPollable.cs b/BizHawk.Emulation.Cores/Consoles/Nintendo/QuickNES/QuickNES.IInputPollable.cs
index 9164bb7653..a83c9d6bc9 100644
--- a/BizHawk.Emulation.Cores/Consoles/Nintendo/QuickNES/QuickNES.IInputPollable.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Nintendo/QuickNES/QuickNES.IInputPollable.cs
@@ -6,7 +6,7 @@ namespace BizHawk.Emulation.Cores.Consoles.Nintendo.QuickNES
 	public partial class QuickNES : IInputPollable
 	{
 		public int LagCount { get; set; }
-		public bool IsLagFrame { get; private set; }
+		public bool IsLagFrame { get; set; }
 
 		public IInputCallbackSystem InputCallbacks
 		{
diff --git a/BizHawk.Emulation.Cores/Consoles/Nintendo/SNES/LibsnesCore.cs b/BizHawk.Emulation.Cores/Consoles/Nintendo/SNES/LibsnesCore.cs
index bb4e65571d..0d1d3e5657 100644
--- a/BizHawk.Emulation.Cores/Consoles/Nintendo/SNES/LibsnesCore.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Nintendo/SNES/LibsnesCore.cs
@@ -740,7 +740,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.SNES
 		int timeFrameCounter;
 		public int Frame { get { return timeFrameCounter; } set { timeFrameCounter = value; } }
 		public int LagCount { get; set; }
-		public bool IsLagFrame { get; private set; }
+		public bool IsLagFrame { get; set; }
 		public string SystemId { get; private set; }
 
 		public string BoardName { get; private set; }
diff --git a/BizHawk.Emulation.Cores/Consoles/PC Engine/PCEngine.cs b/BizHawk.Emulation.Cores/Consoles/PC Engine/PCEngine.cs
index b288ae20ef..c39273e240 100644
--- a/BizHawk.Emulation.Cores/Consoles/PC Engine/PCEngine.cs	
+++ b/BizHawk.Emulation.Cores/Consoles/PC Engine/PCEngine.cs	
@@ -310,7 +310,7 @@ namespace BizHawk.Emulation.Cores.PCEngine
 		bool isLag = false;
 		public int Frame { get { return frame; } set { frame = value; } }
 		public int LagCount { get { return lagCount; } set { lagCount = value; } }
-		public bool IsLagFrame { get { return isLag; } }
+		public bool IsLagFrame { get { return isLag; } set { isLag = value; } }
 
 		private readonly InputCallbackSystem _inputCallbacks = new InputCallbackSystem();
 		public IInputCallbackSystem InputCallbacks { get { return _inputCallbacks; } }
diff --git a/BizHawk.Emulation.Cores/Consoles/Sega/Genesis/Genesis.cs b/BizHawk.Emulation.Cores/Consoles/Sega/Genesis/Genesis.cs
index ef74d601bf..48f1faa3c8 100644
--- a/BizHawk.Emulation.Cores/Consoles/Sega/Genesis/Genesis.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Sega/Genesis/Genesis.cs
@@ -310,7 +310,7 @@ namespace BizHawk.Emulation.Cores.Sega.Genesis
 
 		public int Frame { get; set; }
 		public int LagCount { get { return _lagcount; } set { _lagcount = value; } }
-		public bool IsLagFrame { get { return islag; } }
+		public bool IsLagFrame { get { return islag; } set { islag = value; } }
 		public bool DeterministicEmulation { get { return true; } }
 		public string SystemId { get { return "GEN"; } }
 
diff --git a/BizHawk.Emulation.Cores/Consoles/Sega/SMS/SMS.cs b/BizHawk.Emulation.Cores/Consoles/Sega/SMS/SMS.cs
index fb5f254241..fde4cac977 100644
--- a/BizHawk.Emulation.Cores/Consoles/Sega/SMS/SMS.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Sega/SMS/SMS.cs
@@ -78,7 +78,7 @@ namespace BizHawk.Emulation.Cores.Sega.MasterSystem
 		bool isLag = false;
 		public int Frame { get { return frame; } set { frame = value; } }
 		public int LagCount { get { return lagCount; } set { lagCount = value; } }
-		public bool IsLagFrame { get { return isLag; } }
+		public bool IsLagFrame { get { return isLag; } set { isLag = value; } }
 
 		private readonly InputCallbackSystem _inputCallbacks = new InputCallbackSystem();
 		public IInputCallbackSystem InputCallbacks { get { return _inputCallbacks; } }
diff --git a/BizHawk.Emulation.Cores/Consoles/Sega/Saturn/Yabause.IInputPollable.cs b/BizHawk.Emulation.Cores/Consoles/Sega/Saturn/Yabause.IInputPollable.cs
index 65519c8f89..76fcd17db9 100644
--- a/BizHawk.Emulation.Cores/Consoles/Sega/Saturn/Yabause.IInputPollable.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Sega/Saturn/Yabause.IInputPollable.cs
@@ -10,7 +10,7 @@ namespace BizHawk.Emulation.Cores.Sega.Saturn
 	{
 		public int LagCount { get; set; }
 
-		public bool IsLagFrame { get; private set; }
+		public bool IsLagFrame { get; set; }
 
 		// TODO: optimize managed to unmanaged using the ActiveChanged event
 		public IInputCallbackSystem InputCallbacks
diff --git a/BizHawk.Emulation.Cores/Consoles/Sega/gpgx/GPGX.cs b/BizHawk.Emulation.Cores/Consoles/Sega/gpgx/GPGX.cs
index 77318a76ec..304dc65aee 100644
--- a/BizHawk.Emulation.Cores/Consoles/Sega/gpgx/GPGX.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Sega/gpgx/GPGX.cs
@@ -475,7 +475,7 @@ namespace BizHawk.Emulation.Cores.Consoles.Sega.gpgx
 
 		public int Frame { get; private set; }
 		public int LagCount { get; set; }
-		public bool IsLagFrame { get; private set; }
+		public bool IsLagFrame { get; set; }
 
 		public string SystemId { get { return "GEN"; } }
 		public bool DeterministicEmulation { get { return true; } }
diff --git a/BizHawk.Emulation.Cores/Consoles/Sony/PSX/Octoshock.cs b/BizHawk.Emulation.Cores/Consoles/Sony/PSX/Octoshock.cs
index d9794a467f..d47b89fbf3 100644
--- a/BizHawk.Emulation.Cores/Consoles/Sony/PSX/Octoshock.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Sony/PSX/Octoshock.cs
@@ -769,7 +769,7 @@ namespace BizHawk.Emulation.Cores.Sony.PSX
 
 		public int Frame { get; private set; }
 		public int LagCount { get; set; }
-		public bool IsLagFrame { get; private set; }
+		public bool IsLagFrame { get; set; }
 
 		public IInputCallbackSystem InputCallbacks
 		{
diff --git a/BizHawk.Emulation.Cores/Consoles/WonderSwan/WonderSwan.cs b/BizHawk.Emulation.Cores/Consoles/WonderSwan/WonderSwan.cs
index 5d77013af8..4746759cec 100644
--- a/BizHawk.Emulation.Cores/Consoles/WonderSwan/WonderSwan.cs
+++ b/BizHawk.Emulation.Cores/Consoles/WonderSwan/WonderSwan.cs
@@ -101,7 +101,7 @@ namespace BizHawk.Emulation.Cores.WonderSwan
 
 		public int Frame { get; private set; }
 		public int LagCount { get; set; }
-		public bool IsLagFrame { get; private set; }
+		public bool IsLagFrame { get; set; }
 
 		public string SystemId { get { return "WSWAN"; } }
 		public bool DeterministicEmulation { get; private set; }
diff --git a/BizHawk.Emulation.Cores/Libretro/LibRetroEmulator.cs b/BizHawk.Emulation.Cores/Libretro/LibRetroEmulator.cs
index e67ff90ede..f3028acab3 100644
--- a/BizHawk.Emulation.Cores/Libretro/LibRetroEmulator.cs
+++ b/BizHawk.Emulation.Cores/Libretro/LibRetroEmulator.cs
@@ -903,7 +903,7 @@ namespace BizHawk.Emulation.Cores
 
 		#region IInputPollable
 		public int LagCount { get; set; }
-		public bool IsLagFrame { get; private set; }
+		public bool IsLagFrame { get; set; }
 		public IInputCallbackSystem InputCallbacks
 		{
 			[FeatureNotImplemented]