diff --git a/BizHawk.Emulation/Computers/Commodore64/Cia.cs b/BizHawk.Emulation/Computers/Commodore64/Cia.cs
index 816a16f3b1..889e6a6db2 100644
--- a/BizHawk.Emulation/Computers/Commodore64/Cia.cs
+++ b/BizHawk.Emulation/Computers/Commodore64/Cia.cs
@@ -305,6 +305,7 @@ namespace BizHawk.Emulation.Computers.Commodore64
 		public byte Read(ushort addr)
 		{
 			byte result;
+			addr &= 0xF;
 
 			switch (addr)
 			{
@@ -377,6 +378,7 @@ namespace BizHawk.Emulation.Computers.Commodore64
 
 		public void Write(ushort addr, byte val)
 		{
+			addr &= 0xF;
 			switch (addr)
 			{
 				case 0x00:
diff --git a/BizHawk.Emulation/Computers/Commodore64/MemBus.cs b/BizHawk.Emulation/Computers/Commodore64/MemBus.cs
index 7c129c5b1e..39f57327bf 100644
--- a/BizHawk.Emulation/Computers/Commodore64/MemBus.cs
+++ b/BizHawk.Emulation/Computers/Commodore64/MemBus.cs
@@ -267,6 +267,8 @@ namespace BizHawk.Emulation.Computers.Commodore64
 
 		public void Poke(ushort addr, byte val)
 		{
+			return;
+			/*
 			if (addr == 0x0000)
 			{
 				cpuPort.Direction = val;
@@ -315,6 +317,7 @@ namespace BizHawk.Emulation.Computers.Commodore64
 					ram[addr] = val;
 				}
 			}
+			 */
 		}
 
 		public void PokeRam(int addr, byte val)
diff --git a/BizHawk.Emulation/Computers/Commodore64/VicII.cs b/BizHawk.Emulation/Computers/Commodore64/VicII.cs
index 9fad93ac9e..d8fc017c60 100644
--- a/BizHawk.Emulation/Computers/Commodore64/VicII.cs
+++ b/BizHawk.Emulation/Computers/Commodore64/VicII.cs
@@ -750,6 +750,7 @@ namespace BizHawk.Emulation.Computers.Commodore64
 					PerformSpriteDataFetch(7);
 					break;
 				case 10:
+					signal.VicAEC = true;
 					PerformDRAMRefresh();
 					break;
 				case 11:
@@ -889,6 +890,7 @@ namespace BizHawk.Emulation.Computers.Commodore64
 					PerformSpriteComparison();
 					break;
 				case 55:
+					signal.VicAEC = true;
 					PerformSpriteComparison();
 					break;
 				case 56:
@@ -960,9 +962,6 @@ namespace BizHawk.Emulation.Computers.Commodore64
 
 		private void PerformSpriteComparison()
 		{
-			// reenable cpu if disabled
-			signal.VicAEC = true;
-
 			// sprite comparison
 			for (int i = 0; i < 8; i++)
 			{
@@ -985,7 +984,6 @@ namespace BizHawk.Emulation.Computers.Commodore64
 		private void PerformSpriteDataFetch(int spriteIndex)
 		{
 			// second half of the fetch cycle
-			signal.VicAEC = !regs.MDMA[spriteIndex];
 			if (regs.MDMA[spriteIndex])
 			{
 				for (int i = 0; i < 2; i++)