diff --git a/desmume/src/NDSSystem.cpp b/desmume/src/NDSSystem.cpp
index d01e06c80..2d56bea3f 100755
--- a/desmume/src/NDSSystem.cpp
+++ b/desmume/src/NDSSystem.cpp
@@ -2645,7 +2645,7 @@ void NDS_Reset()
 	bool didLoadExtFirmware = false;
 	extFirmwareObj = new CFIRMWARE();
 	
-	if (CommonSettings.UseExtFirmware)
+	if (CommonSettings.UseExtFirmware && NDS_ARM7.BIOS_loaded && NDS_ARM9.BIOS_loaded)
 	{
 		didLoadExtFirmware = extFirmwareObj->load(CommonSettings.ExtFirmwarePath);
 	}
@@ -2673,7 +2673,7 @@ void NDS_Reset()
 	//1. we have the ARM7 and ARM9 bioses (its doubtful that our HLE bios implement the necessary functions)
 	//2. firmware is available
 	//3. user has requested booting from firmware
-	bool canBootFromFirmware = (NDS_ARM7.BIOS_loaded && NDS_ARM9.BIOS_loaded && CommonSettings.BootFromFirmware && didLoadExtFirmware);
+	bool canBootFromFirmware = (CommonSettings.BootFromFirmware && didLoadExtFirmware);
 	bool bootResult = false;
 	
 	if (canBootFromFirmware)
diff --git a/desmume/src/frontend/cocoa/cocoa_core.mm b/desmume/src/frontend/cocoa/cocoa_core.mm
index cf5ff0a46..3ca245346 100644
--- a/desmume/src/frontend/cocoa/cocoa_core.mm
+++ b/desmume/src/frontend/cocoa/cocoa_core.mm
@@ -448,6 +448,7 @@ volatile bool execute = true;
 - (void) setEmuFlagUseExternalBios:(BOOL)enable
 {
 	execControl->SetEnableExternalBIOS((enable) ? true : false);
+	[self updateFirmwareMACAddressString];
 }
 
 - (BOOL) emuFlagUseExternalBios
@@ -743,7 +744,7 @@ volatile bool execute = true;
 
 - (void) updateFirmwareMACAddressString
 {
-	if ([self emuFlagUseExternalFirmware])
+	if ([self emuFlagUseExternalBios] && [self emuFlagUseExternalFirmware])
 	{
 		[self setFirmwareMACAddressSelectionString:[NSString stringWithFormat:@"Ext. Firmware  %@", [self extFirmwareMACAddressString]]];
 	}
@@ -854,7 +855,7 @@ volatile bool execute = true;
 {
 	[self setCoreState:ExecutionBehavior_Pause];
 	
-	if (![self emuFlagUseExternalFirmware])
+	if (![self emuFlagUseExternalBios] || ![self emuFlagUseExternalFirmware])
 	{
 		[[self cdsFirmware] writeUserDefaultWFCUserID];
 		[[self cdsFirmware] updateFirmwareConfigSessionValues];
diff --git a/desmume/src/frontend/cocoa/userinterface/EmuControllerDelegate.mm b/desmume/src/frontend/cocoa/userinterface/EmuControllerDelegate.mm
index 102dcdea8..2b2fc752e 100644
--- a/desmume/src/frontend/cocoa/userinterface/EmuControllerDelegate.mm
+++ b/desmume/src/frontend/cocoa/userinterface/EmuControllerDelegate.mm
@@ -1709,7 +1709,7 @@
 	[self pauseCore];
 	
 	CocoaDSCore *cdsCore = (CocoaDSCore *)[cdsCoreController content];
-	if (![cdsCore emuFlagUseExternalFirmware])
+	if (![cdsCore emuFlagUseExternalBios] || ![cdsCore emuFlagUseExternalFirmware])
 	{
 		[[cdsCore cdsFirmware] updateFirmwareConfigSessionValues];
 	}
@@ -1914,7 +1914,7 @@
 	}
 	
 	// Unload the ROM.
-	if (![cdsCore emuFlagUseExternalFirmware])
+	if (![cdsCore emuFlagUseExternalBios] || ![cdsCore emuFlagUseExternalFirmware])
 	{
 		[[cdsCore cdsFirmware] writeUserDefaultWFCUserID];
 	}