diff --git a/Core/EventManager.cpp b/Core/EventManager.cpp
index 5be0198..e2b807e 100644
--- a/Core/EventManager.cpp
+++ b/Core/EventManager.cpp
@@ -268,7 +268,7 @@ void EventManager::GetDisplayBuffer(uint32_t *buffer, uint32_t bufferSize, Event
 {
 	auto lock = _lock.AcquireSafe();
 
-	if(bufferSize < _scanlineCount * 2 * EventManager::ScanlineWidth * 4) {
+	if(_snapshotScanline < 0 || bufferSize < _scanlineCount * 2 * EventManager::ScanlineWidth * 4) {
 		return;
 	}
 
diff --git a/Core/GbDmaController.h b/Core/GbDmaController.h
index 0613237..0b02cf0 100644
--- a/Core/GbDmaController.h
+++ b/Core/GbDmaController.h
@@ -6,7 +6,7 @@
 class GbMemoryManager;
 class GbPpu;
 
-class GbDmaController : public ISerializable
+class GbDmaController final : public ISerializable
 {
 private:
 	GbDmaControllerState _state;
@@ -17,6 +17,7 @@ private:
 
 public:
 	GbDmaController(GbMemoryManager* memoryManager, GbPpu* ppu);
+
 	void Exec();
 
 	bool IsOamDmaRunning();
diff --git a/Core/GbEventManager.cpp b/Core/GbEventManager.cpp
index b701e8e..aad38ad 100644
--- a/Core/GbEventManager.cpp
+++ b/Core/GbEventManager.cpp
@@ -118,7 +118,7 @@ void GbEventManager::FilterEvents(EventViewerDisplayOptions& options)
 					showEvent = isWrite ? options.ShowPpuRegisterBgScrollWrites : options.ShowPpuRegisterReads;
 				} else if(reg >= 0x8000 && reg <= 0x9FFF) {
 					showEvent = isWrite ? options.ShowPpuRegisterVramWrites : options.ShowPpuRegisterReads;
-				} else if(reg >= 0xFF47 && reg <= 0xFF49 || (reg >= 0xFF68 && reg <= 0xFF6B)) {
+				} else if((reg >= 0xFF47 && reg <= 0xFF49) || (reg >= 0xFF68 && reg <= 0xFF6B)) {
 					showEvent = isWrite ? options.ShowPpuRegisterCgramWrites : options.ShowPpuRegisterReads;
 				} else if(reg >= 0xFF4A && reg <= 0xFF4B) {
 					showEvent = isWrite ? options.ShowPpuRegisterWindowWrites : options.ShowPpuRegisterReads;
@@ -155,7 +155,7 @@ void GbEventManager::DrawEvent(DebugEventInfo& evt, bool drawBackground, uint32_
 				color = isWrite ? options.PpuRegisterWriteBgScrollColor : ppuReadColor;
 			} else if(reg >= 0x8000 && reg <= 0x9FFF) {
 				color = isWrite ? options.PpuRegisterWriteVramColor : ppuReadColor;
-			} else if(reg >= 0xFF47 && reg <= 0xFF49 || (reg >= 0xFF68 && reg <= 0xFF6B)) {
+			} else if((reg >= 0xFF47 && reg <= 0xFF49) || (reg >= 0xFF68 && reg <= 0xFF6B)) {
 				color = isWrite ? options.PpuRegisterWriteCgramColor : ppuReadColor;
 			} else if(reg >= 0xFF4A && reg <= 0xFF4B) {
 				color = isWrite ? options.PpuRegisterWriteWindowColor : ppuReadColor;
@@ -222,7 +222,7 @@ void GbEventManager::GetDisplayBuffer(uint32_t* buffer, uint32_t bufferSize, Eve
 {
 	auto lock = _lock.AcquireSafe();
 
-	if(bufferSize < _scanlineCount * 2 * GbEventManager::ScanlineWidth * 4) {
+	if(_snapshotScanline < 0 || bufferSize < _scanlineCount * 2 * GbEventManager::ScanlineWidth * 4) {
 		return;
 	}
 
diff --git a/Core/GbEventManager.h b/Core/GbEventManager.h
index 0ecc107..29ea6f2 100644
--- a/Core/GbEventManager.h
+++ b/Core/GbEventManager.h
@@ -27,7 +27,7 @@ private:
 	vector<DebugEventInfo> _sentEvents;
 
 	vector<DebugEventInfo> _snapshot;
-	uint16_t _snapshotScanline = 0;
+	int16_t _snapshotScanline = -1;
 	uint16_t _snapshotCycle = 0;
 	SimpleLock _lock;