diff --git a/Core/Console.cpp b/Core/Console.cpp
index ee61be78..fb6a1c4e 100644
--- a/Core/Console.cpp
+++ b/Core/Console.cpp
@@ -473,10 +473,10 @@ void Console::ProcessCpuClock()
 
 void Console::ProcessInterferenceAudio()
 {
-	_InvA13 = _ppu->_A13pinLowSum;
-	_ppu->_A13pinLowSum = 0;
+	_InvA13 = (_ppu->_A13pinLow == 1) ? 0 : 1; // invert relative to 2A03
 
-	_InvOE1 = !_controlManager->GetInvOE1(_controlManager->_address); // invert relative to 2A03
+	_controlManager->GetInvOE1(_controlManager->_address);
+	_InvOE1 = (_controlManager->_OE1pinLow == 1) ? 0 : 1; // invert relative to 2A03
 
 	if (_controlManager->_strobed == true)
 		_controlManager->_strobed = false;
diff --git a/Core/ControlManager.cpp b/Core/ControlManager.cpp
index bc5045ef..9e80e937 100644
--- a/Core/ControlManager.cpp
+++ b/Core/ControlManager.cpp
@@ -351,12 +351,11 @@ void ControlManager::WriteRAM(uint16_t addr, uint8_t value)
 	}
 }
 
-bool ControlManager::GetInvOE1(uint16_t addr)
+void ControlManager::GetInvOE1(uint16_t addr)
 {
 	// pull low for only one clock
 	if (addr == 0x4016)
-		_OE1pinLow = !_strobed;
-	return _OE1pinLow;
+		_OE1pinLow = (_strobed) ? 0 : 1;
 }
 
 void ControlManager::Reset(bool softReset)
diff --git a/Core/ControlManager.h b/Core/ControlManager.h
index 1b590734..976ecb9e 100644
--- a/Core/ControlManager.h
+++ b/Core/ControlManager.h
@@ -43,7 +43,7 @@ protected:
 	virtual uint8_t GetOpenBusMask(uint8_t port);
 
 public:
-	bool _OE1pinLow;
+	uint8_t _OE1pinLow;
 	uint16_t _address;
 	bool _strobed;
 
@@ -85,5 +85,5 @@ public:
 	virtual uint8_t ReadRAM(uint16_t addr) override;
 	virtual void WriteRAM(uint16_t addr, uint8_t value) override;
 
-	bool GetInvOE1(uint16_t addr);
+	void GetInvOE1(uint16_t addr);
 };
diff --git a/Core/PPU.cpp b/Core/PPU.cpp
index 1ee1d1bb..81b6edda 100644
--- a/Core/PPU.cpp
+++ b/Core/PPU.cpp
@@ -466,7 +466,7 @@ void PPU::WriteRAM(uint16_t addr, uint8_t value)
 void PPU::GetInvA13()
 {
 	// pull level high when PPU/VRAM addr bit 13 is low
-	_A13pinLowSum += (bool)(_ppuBusAddress & 0x2000); // invert relative to 2A03
+	_A13pinLow = (_ppuBusAddress & 0x2000) ? 0 : 1;
 }
 
 uint8_t PPU::ReadPaletteRAM(uint16_t addr)
diff --git a/Core/PPU.h b/Core/PPU.h
index f68f9454..7d097003 100644
--- a/Core/PPU.h
+++ b/Core/PPU.h
@@ -180,7 +180,7 @@ class PPU : public IMemoryHandler, public Snapshotable
 		static constexpr int32_t OutputBufferSize = 256*240*2;
 		static constexpr int32_t OamDecayCycleCount = 3000;
 		
-		uint8_t _A13pinLowSum;
+		uint8_t _A13pinLow;
 
 		PPU(shared_ptr<Console> console);
 		virtual ~PPU();
diff --git a/Core/SoundMixer.cpp b/Core/SoundMixer.cpp
index 854e2cda..7446f193 100644
--- a/Core/SoundMixer.cpp
+++ b/Core/SoundMixer.cpp
@@ -277,8 +277,8 @@ int16_t SoundMixer::GetOutputVolume(bool forRightChannel)
 #endif
 		GetChannelOutput(AudioChannel::EPSM_L, forRightChannel) * 4 +
 		GetChannelOutput(AudioChannel::EPSM_R, forRightChannel) * 4 +
-		(GetChannelOutput(AudioChannel::InvA13, forRightChannel) * 20) / 3.0 + // 3 PPU samples per CPU clock
-		GetChannelOutput(AudioChannel::InvOE1, forRightChannel) * 100
+		GetChannelOutput(AudioChannel::InvA13, forRightChannel) * 20 +
+		GetChannelOutput(AudioChannel::InvOE1, forRightChannel) * 1000
 	);
 }