diff --git a/BizHawk.Emulation.Cores/Consoles/Nintendo/Gameboy/Gambatte.ISettable.cs b/BizHawk.Emulation.Cores/Consoles/Nintendo/Gameboy/Gambatte.ISettable.cs
index 3cb8414cb4..fb41292935 100644
--- a/BizHawk.Emulation.Cores/Consoles/Nintendo/Gameboy/Gambatte.ISettable.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Nintendo/Gameboy/Gambatte.ISettable.cs
@@ -85,16 +85,17 @@ namespace BizHawk.Emulation.Cores.Nintendo.Gameboy
 			[DefaultValue(false)]
 			public bool EnableBIOS { get; set; }
 
-			[DisplayName("Console Mode")]
-			[Description("Pick which console to run, 'Default' chooses from ROM extension, 'GB' and 'GBC' chooses the respective system")]
-			[DefaultValue("Default")]
-			public string ConsoleMode
+			public enum ConsoleModeType
 			{
-				get { return _ConsoleMode; }
-				set { _ConsoleMode = value;}
+				Auto,
+				GB,
+				GBC
 			}
-			[JsonIgnore]
-			private string _ConsoleMode;
+
+			[DisplayName("Console Mode")]
+			[Description("Pick which console to run, 'Auto' chooses from ROM header, 'GB' and 'GBC' chooses the respective system")]
+			[DefaultValue(ConsoleModeType.Auto)]
+			public ConsoleModeType ConsoleMode { get; set; }
 
 			[DisplayName("CGB in GBA")]
 			[Description("Emulate GBA hardware running a CGB game, instead of CGB hardware.  Relevant only for titles that detect the presense of a GBA, such as Shantae.")]
diff --git a/BizHawk.Emulation.Cores/Consoles/Nintendo/Gameboy/Gambatte.cs b/BizHawk.Emulation.Cores/Consoles/Nintendo/Gameboy/Gambatte.cs
index 7b2d03c371..dd2b855fba 100644
--- a/BizHawk.Emulation.Cores/Consoles/Nintendo/Gameboy/Gambatte.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Nintendo/Gameboy/Gambatte.cs
@@ -58,12 +58,10 @@ namespace BizHawk.Emulation.Cores.Nintendo.Gameboy
 
 			if (game.System == "GB")
 			{
-				BiosRom = new byte[256];
 				BiosRom = comm.CoreFileProvider.GetFirmware("GB", "World", false);
 			}
 			else
 			{
-				BiosRom = new byte[2304];
 				BiosRom = comm.CoreFileProvider.GetFirmware("GBC", "World", false);
 			}
 
@@ -80,32 +78,25 @@ namespace BizHawk.Emulation.Cores.Nintendo.Gameboy
 
 				LibGambatte.LoadFlags flags = 0;
 
-				if (_syncSettings.ConsoleMode=="GB")
+				switch (_syncSettings.ConsoleMode)
 				{
-					flags |= LibGambatte.LoadFlags.FORCE_DMG;
-					
-					// we need to change the BIOS to GB bios
-					if (game.System == "GBC")
-					{
-						BiosRom = null;
-						BiosRom = new byte[256];
-						BiosRom = comm.CoreFileProvider.GetFirmware("GB", "World", false);
-						bios_length = BiosRom.Length;
-					}
-					
-				}
-				else if (_syncSettings.ConsoleMode == "GBC")
-				{
-					BiosRom = null;
-					BiosRom = new byte[2304];
-					BiosRom = comm.CoreFileProvider.GetFirmware("GBC", "World", false);
-					bios_length = BiosRom.Length;
-
-				}
-				else
-				{
-					 if(game.System == "GB")
+					case GambatteSyncSettings.ConsoleModeType.GB:
 						flags |= LibGambatte.LoadFlags.FORCE_DMG;
+						// we need to change the BIOS to GB bios
+						if (game.System == "GBC")
+						{
+							BiosRom = comm.CoreFileProvider.GetFirmware("GB", "World", false);
+							bios_length = BiosRom.Length;
+						}
+						break;
+					case GambatteSyncSettings.ConsoleModeType.GBC:
+						BiosRom = comm.CoreFileProvider.GetFirmware("GBC", "World", false);
+						bios_length = BiosRom.Length;
+						break;
+					default:
+						if (game.System == "GB")
+							flags |= LibGambatte.LoadFlags.FORCE_DMG;
+						break;
 				}
 
 				if (_syncSettings.EnableBIOS && BiosRom == null)
@@ -351,7 +342,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.Gameboy
 
 			LibGambatte.gambatte_settracecallback(GambatteState, _tracecb);
 
-			LibGambatte.gambatte_setlayers(GambatteState, (_settings.DisplayBG ? 1 : 0) | (_settings.DisplayOBJ ? 2 : 0) | (_settings.DisplayWindow ? 4 : 0 ) );
+			LibGambatte.gambatte_setlayers(GambatteState, (_settings.DisplayBG ? 1 : 0) | (_settings.DisplayOBJ ? 2 : 0) | (_settings.DisplayWindow ? 4 : 0));
 		}
 
 		internal void FrameAdvancePost()