diff --git a/source/CardManager.cpp b/source/CardManager.cpp
index 5ae06174..67739753 100644
--- a/source/CardManager.cpp
+++ b/source/CardManager.cpp
@@ -160,6 +160,7 @@ void CardManager::RemoveInternal(UINT slot)
 			break;
 		}
 
+		UnregisterIoHandler(slot);
 		delete m_slot[slot];
 		m_slot[slot] = NULL;
 	}
diff --git a/source/Configuration/PropertySheetHelper.cpp b/source/Configuration/PropertySheetHelper.cpp
index 6f296976..475c7b44 100644
--- a/source/Configuration/PropertySheetHelper.cpp
+++ b/source/Configuration/PropertySheetHelper.cpp
@@ -28,6 +28,7 @@ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 
 #include "../Windows/AppleWin.h"	// g_nAppMode, g_uScrollLockToggle, sg_PropertySheet
 #include "../CardManager.h"
+#include "../Memory.h"
 #include "../Disk.h"
 #include "../Log.h"
 #include "../Registry.h"
@@ -130,6 +131,7 @@ void CPropertySheetHelper::SetSlot(UINT slot, SS_CARDTYPE newCardType)
 		return;
 
 	GetCardMgr().Insert(slot, newCardType);
+	GetCardMgr().GetRef(slot).InitializeIO(GetCxRomPeripheral());
 }
 
 // Used by:
diff --git a/source/Disk.cpp b/source/Disk.cpp
index 65993c58..8dd5a6aa 100644
--- a/source/Disk.cpp
+++ b/source/Disk.cpp
@@ -74,10 +74,6 @@ Disk2InterfaceCard::Disk2InterfaceCard(UINT slot) :
 
 	ResetLogicStateSequencer();
 
-	// if created by user in Config->Disk, then MemInitializeIO() won't be called
-	if (GetCxRomPeripheral())
-		InitializeIO(GetCxRomPeripheral());	// During regular start-up, Initialize() will be called later by MemInitializeIO()
-
 	// Debug:
 #if LOG_DISK_NIBBLES_USE_RUNTIME_VAR
 	m_bLogDisk_NibblesRW = false;
@@ -92,9 +88,6 @@ Disk2InterfaceCard::~Disk2InterfaceCard(void)
 {
 	EjectDiskInternal(DRIVE_1);
 	EjectDiskInternal(DRIVE_2);
-
-	// if destroyed by user in Config->Disk, then ensure that old object's reference is removed
-	UnregisterIoHandler(m_slot);
 }
 
 bool Disk2InterfaceCard::GetEnhanceDisk(void) { return m_enhanceDisk; }
diff --git a/source/Harddisk.cpp b/source/Harddisk.cpp
index fe373b3e..67a96c19 100644
--- a/source/Harddisk.cpp
+++ b/source/Harddisk.cpp
@@ -143,19 +143,12 @@ HarddiskInterfaceCard::HarddiskInterfaceCard(UINT slot) :
 	m_notBusyCycle = 0;
 
 	m_saveDiskImage = true;	// Save the DiskImage name to Registry
-
-	// if created by user in Config->Disk, then MemInitializeIO() won't be called
-	if (GetCxRomPeripheral())
-		InitializeIO(GetCxRomPeripheral());	// During regular start-up, Initialize() will be called later by MemInitializeIO()
 }
 
 HarddiskInterfaceCard::~HarddiskInterfaceCard(void)
 {
 	CleanupDriveInternal(HARDDISK_1);
 	CleanupDriveInternal(HARDDISK_2);
-
-	// if destroyed by user in Config->Disk, then ensure that old object's reference is removed
-	UnregisterIoHandler(m_slot);
 }
 
 void HarddiskInterfaceCard::Reset(const bool powerCycle)