diff --git a/BizHawk.Emulation.Cores/Consoles/Nintendo/GBHawk/GBHawk.ISettable.cs b/BizHawk.Emulation.Cores/Consoles/Nintendo/GBHawk/GBHawk.ISettable.cs
index 2aa660953b..da4d606465 100644
--- a/BizHawk.Emulation.Cores/Consoles/Nintendo/GBHawk/GBHawk.ISettable.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Nintendo/GBHawk/GBHawk.ISettable.cs
@@ -137,6 +137,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBHawk
 
 			[JsonIgnore]
 			private int _RTCInitialTime;
+			[JsonIgnore]
 			private int _RTCOffset;
 			[JsonIgnore]
 			public ushort _DivInitialTime = 8;
diff --git a/BizHawk.Emulation.Cores/Consoles/Nintendo/GBHawkLink/GBHawkLink.ISettable.cs b/BizHawk.Emulation.Cores/Consoles/Nintendo/GBHawkLink/GBHawkLink.ISettable.cs
index c609a28515..73046bdbac 100644
--- a/BizHawk.Emulation.Cores/Consoles/Nintendo/GBHawkLink/GBHawkLink.ISettable.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Nintendo/GBHawkLink/GBHawkLink.ISettable.cs
@@ -145,11 +145,15 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBHawkLink
 
 			[JsonIgnore]
 			private int _RTCInitialTime_L;
+			[JsonIgnore]
 			private int _RTCInitialTime_R;
+			[JsonIgnore]
 			private int _RTCOffset_L;
+			[JsonIgnore]
 			private int _RTCOffset_R;
 			[JsonIgnore]
 			public ushort _DivInitialTime_L = 8;
+			[JsonIgnore]
 			public ushort _DivInitialTime_R = 8;
 
 			public GBLinkSyncSettings Clone()
diff --git a/BizHawk.Emulation.Cores/Consoles/Nintendo/GBHawkLink3x/GBHawkLink3x.ISettable.cs b/BizHawk.Emulation.Cores/Consoles/Nintendo/GBHawkLink3x/GBHawkLink3x.ISettable.cs
index 9c0adf8f7b..0e959567d2 100644
--- a/BizHawk.Emulation.Cores/Consoles/Nintendo/GBHawkLink3x/GBHawkLink3x.ISettable.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Nintendo/GBHawkLink3x/GBHawkLink3x.ISettable.cs
@@ -183,14 +183,21 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBHawkLink3x
 
 			[JsonIgnore]
 			private int _RTCInitialTime_L;
+			[JsonIgnore]
 			private int _RTCInitialTime_C;
+			[JsonIgnore]
 			private int _RTCInitialTime_R;
+			[JsonIgnore]
 			private int _RTCOffset_L;
+			[JsonIgnore]
 			private int _RTCOffset_C;
+			[JsonIgnore]
 			private int _RTCOffset_R;
 			[JsonIgnore]
 			public ushort _DivInitialTime_L = 8;
+			[JsonIgnore]
 			public ushort _DivInitialTime_C = 8;
+			[JsonIgnore]
 			public ushort _DivInitialTime_R = 8;
 
 			public GBLink3xSyncSettings Clone()
diff --git a/BizHawk.Emulation.Cores/Consoles/Nintendo/GBHawkLink4x/GBHawkLink4x.ISettable.cs b/BizHawk.Emulation.Cores/Consoles/Nintendo/GBHawkLink4x/GBHawkLink4x.ISettable.cs
index b509dd1d3c..0ada335d84 100644
--- a/BizHawk.Emulation.Cores/Consoles/Nintendo/GBHawkLink4x/GBHawkLink4x.ISettable.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Nintendo/GBHawkLink4x/GBHawkLink4x.ISettable.cs
@@ -221,17 +221,27 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBHawkLink4x
 
 			[JsonIgnore]
 			private int _RTCInitialTime_A;
+			[JsonIgnore]
 			private int _RTCInitialTime_B;
+			[JsonIgnore]
 			private int _RTCInitialTime_C;
+			[JsonIgnore]
 			private int _RTCInitialTime_D;
+			[JsonIgnore]
 			private int _RTCOffset_A;
+			[JsonIgnore]
 			private int _RTCOffset_B;
+			[JsonIgnore]
 			private int _RTCOffset_C;
+			[JsonIgnore]
 			private int _RTCOffset_D;
 			[JsonIgnore]
 			public ushort _DivInitialTime_A = 8;
+			[JsonIgnore]
 			public ushort _DivInitialTime_B = 8;
+			[JsonIgnore]
 			public ushort _DivInitialTime_C = 8;
+			[JsonIgnore]
 			public ushort _DivInitialTime_D = 8;
 
 			public GBLink4xSyncSettings Clone()