diff --git a/AppleWin/source/Disk.cpp b/AppleWin/source/Disk.cpp
index 892c4903..5a4978da 100644
--- a/AppleWin/source/Disk.cpp
+++ b/AppleWin/source/Disk.cpp
@@ -759,19 +759,11 @@ void DiskLoadRom(LPBYTE pCxRomPeripheral, UINT uSlot)
 
 	memcpy(pCxRomPeripheral + uSlot*APPLE_SLOT_SIZE, pData, DISK2_FW_SIZE);
 
-	if (enhancedisk)
-	{
-		// Disable the track stepping delay in the Disk II controller firmware
-		*(pCxRomPeripheral + (uSlot*APPLE_SLOT_SIZE) + 0x4C) = 0xA9;
-		*(pCxRomPeripheral + (uSlot*APPLE_SLOT_SIZE) + 0x4D) = 0x00;
-		*(pCxRomPeripheral + (uSlot*APPLE_SLOT_SIZE) + 0x4E) = 0xEA;
-
-		// The following maintains the firmware's ADC checksum (used by "The CIA Files")
-		// Correcting for both ADC and EOR checksums is not possible in this case.
-		*(pCxRomPeripheral + (uSlot*APPLE_SLOT_SIZE) + 0x4B) = 0x87; // was 0x56
-	}
-
-	//
+	// NB. We used to disable the track stepping delay in the Disk II controller firmware by
+	// patching $C64C with $A9,$00,$EA. Now not doing this since:
+	// . Authentic Speed should be authentic
+	// . Enhanced Speed runs emulation unthrottled, so removing the delay has negligible effect
+	// . Patching the f/w breaks the ADC & EOR checksums used by "The CIA Files" (Tricy Dick)
 
 	RegisterIoHandler(uSlot, Disk_IORead, Disk_IOWrite, NULL, NULL, NULL, NULL);
 }