diff --git a/LEGO1/mxdiskstreamcontroller.h b/LEGO1/mxdiskstreamcontroller.h
index a69c28d8..28966d9d 100644
--- a/LEGO1/mxdiskstreamcontroller.h
+++ b/LEGO1/mxdiskstreamcontroller.h
@@ -39,6 +39,11 @@ class MxDiskStreamController : public MxStreamController {
 		return !strcmp(p_name, MxDiskStreamController::ClassName()) || MxStreamController::IsA(p_name);
 	}
 
+	inline MxBool GetUnk0xc4() const { return m_unk0xc4; }
+
+	void FUN_100c7f40(MxDSStreamingAction* p_streamingaction);
+	void FUN_100c8670(MxDSStreamingAction* p_streamingAction);
+
 private:
 	MxStreamListMxDSAction m_list0x64; // 0x64
 	undefined m_unk0x70;               // 0x70
@@ -48,7 +53,7 @@ class MxDiskStreamController : public MxStreamController {
 	MxStreamListMxDSAction m_list0x90; // 0x90
 	MxCriticalSection m_critical9c;    // 0x9c
 	MxStreamListMxDSAction m_list0xb8; // 0xb8
-	undefined m_unk0xc4;               // 0xc4
+	MxBool m_unk0xc4;                  // 0xc4
 
 	MxResult FUN_100c7890(MxDSStreamingAction* p_action);
 	void FUN_100c7970();
@@ -57,12 +62,10 @@ class MxDiskStreamController : public MxStreamController {
 	MxResult FUN_100c7d10();
 	void FUN_100c7980();
 	MxDSStreamingAction* FUN_100c7db0();
-	void FUN_100c7f40(MxDSStreamingAction* p_streamingaction);
 	MxResult FUN_100c8360(MxDSStreamingAction* p_action);
 	void InsertToList74(MxDSBuffer* p_buffer);
 	void FUN_100c8540();
 	void FUN_100c8720();
-	void FUN_100c8670(MxDSStreamingAction* p_streamingAction);
 };
 
 // TEMPLATE: LEGO1 0x100c7330
diff --git a/LEGO1/mxdiskstreamprovider.cpp b/LEGO1/mxdiskstreamprovider.cpp
index b9118db8..bba524a2 100644
--- a/LEGO1/mxdiskstreamprovider.cpp
+++ b/LEGO1/mxdiskstreamprovider.cpp
@@ -1,6 +1,7 @@
 #include "mxdiskstreamprovider.h"
 
 #include "mxautolocker.h"
+#include "mxdiskstreamcontroller.h"
 #include "mxdsbuffer.h"
 #include "mxdsstreamingaction.h"
 #include "mxomni.h"
@@ -131,8 +132,56 @@ MxResult MxDiskStreamProvider::FUN_100d1780(MxDSStreamingAction* p_action)
 // FUNCTION: LEGO1 0x100d18f0
 void MxDiskStreamProvider::PerformWork()
 {
-	// TODO
-	OutputDebugStringA("work is not being preformed.\n");
+	MxDSStreamingAction* action;
+	{
+		MxAutoLocker lock(&m_criticalSection);
+		if (m_list.size() != 0 && !FUN_100d1af0((MxDSStreamingAction*)m_list.front())) {
+			MxThread::Sleep(500);
+			m_busySemaphore.Release(1);
+			return;
+		}
+	}
+
+	{
+		MxAutoLocker lock(&m_criticalSection);
+		if (m_list.size() != 0) {
+			action = (MxDSStreamingAction*)m_list.front();
+			m_list.pop_front();
+
+			// TODO delete lock here (could be an line function)
+			if (action->GetUnknowna0()->GetWriteOffset() < 0x20000) {
+				g_unk0x10102878--;
+			}
+
+			MxDSBuffer* buffer = action->GetUnknowna0();
+			if (m_pFile->GetPosition() == action->GetUnknowna0()->GetWriteOffset() ||
+				m_pFile->Seek(action->GetBufferOffset(), 0) == 0) {
+				buffer->SetUnknown14(m_pFile->GetPosition());
+				if (m_pFile->ReadToBuffer(buffer) == SUCCESS) {
+					buffer->SetUnknown1c(m_pFile->GetPosition());
+					if (action->GetUnknown9c() < 1) {
+						if (m_pLookup == NULL || !((MxDiskStreamController*) m_pLookup)->GetUnk0xc4()) {
+							((MxDiskStreamController*) m_pLookup)->FUN_100c8670(action);
+						}
+						else {
+							((MxDiskStreamController*) m_pLookup)->FUN_100c7f40(action);
+						}
+					}
+					else {
+						FUN_100d1b20(action);
+					}
+
+					action = NULL;
+				}
+			}
+		}
+	}
+
+	if (action)
+	{
+		((MxDiskStreamController*) m_pLookup)->FUN_100c8670(action);
+	}
+	MxThread::Sleep(0);
 }
 
 // FUNCTION: LEGO1 0x100d1af0
@@ -145,6 +194,13 @@ MxBool MxDiskStreamProvider::FUN_100d1af0(MxDSStreamingAction* p_action)
 	return TRUE;
 }
 
+// STUB: LEGO1 0x100d1b20
+MxResult MxDiskStreamProvider::FUN_100d1b20(MxDSStreamingAction* p_action)
+{
+	OutputDebugString("MxDiskStreamProvider::FUN_100d1b20");
+	return FAILURE;
+}
+
 // FUNCTION: LEGO1 0x100d1e90
 MxU32 MxDiskStreamProvider::GetFileSize()
 {
diff --git a/LEGO1/mxdiskstreamprovider.h b/LEGO1/mxdiskstreamprovider.h
index 80719ab0..4f54a3ed 100644
--- a/LEGO1/mxdiskstreamprovider.h
+++ b/LEGO1/mxdiskstreamprovider.h
@@ -47,6 +47,7 @@ class MxDiskStreamProvider : public MxStreamProvider {
 	MxResult FUN_100d1780(MxDSStreamingAction* p_action);
 	void PerformWork();
 	static MxBool FUN_100d1af0(MxDSStreamingAction* p_action);
+	MxResult FUN_100d1b20(MxDSStreamingAction* p_action);
 
 	virtual MxResult SetResourceToGet(MxStreamController* p_resource) override; // vtable+0x14
 	virtual MxU32 GetFileSize() override;                                       // vtable+0x18
diff --git a/LEGO1/mxdsbuffer.h b/LEGO1/mxdsbuffer.h
index f396a9e2..ac003711 100644
--- a/LEGO1/mxdsbuffer.h
+++ b/LEGO1/mxdsbuffer.h
@@ -62,6 +62,8 @@ class MxDSBuffer : public MxCore {
 	inline MxU32 GetWriteOffset() { return m_writeOffset; }
 	inline MxU16 GetRefCount() { return m_refcount; }
 	inline MxDSBufferType GetMode() { return m_mode; }
+	inline void SetUnknown14(undefined4 p_unk0x14) { m_unk0x14 = p_unk0x14; }
+	inline void SetUnknown1c(undefined4 p_unk0x1c) { m_unk0x1c = p_unk0x1c; }
 
 private:
 	MxU8* m_pBuffer;                // 0x08
diff --git a/LEGO1/mxdssource.cpp b/LEGO1/mxdssource.cpp
index c38799d3..4e4cf65d 100644
--- a/LEGO1/mxdssource.cpp
+++ b/LEGO1/mxdssource.cpp
@@ -3,9 +3,9 @@
 #include "mxdsbuffer.h"
 
 // FUNCTION: LEGO1 0x100bffd0
-void MxDSSource::ReadToBuffer(MxDSBuffer* p_buffer)
+MxResult MxDSSource::ReadToBuffer(MxDSBuffer* p_buffer)
 {
-	Read(p_buffer->GetBuffer(), p_buffer->GetWriteOffset());
+	return Read(p_buffer->GetBuffer(), p_buffer->GetWriteOffset());
 }
 
 // FUNCTION: LEGO1 0x100bfff0
diff --git a/LEGO1/mxdssource.h b/LEGO1/mxdssource.h
index 724efca5..c38d1e50 100644
--- a/LEGO1/mxdssource.h
+++ b/LEGO1/mxdssource.h
@@ -23,15 +23,16 @@ class MxDSSource : public MxCore {
 		return !strcmp(p_name, MxDSSource::ClassName()) || MxCore::IsA(p_name);
 	}
 
-	virtual MxLong Open(MxULong) = 0;
-	virtual MxLong Close() = 0;
-	virtual void ReadToBuffer(MxDSBuffer* p_buffer);
-	virtual MxResult Read(unsigned char*, MxULong) = 0;
-	virtual MxLong Seek(MxLong, int) = 0;
-	virtual MxULong GetBufferSize() = 0;
-	virtual MxULong GetStreamBuffersNum() = 0;
-	virtual MxLong GetLengthInDWords();
-	virtual MxU32* GetBuffer(); // 0x34
+	virtual MxLong Open(MxULong) = 0;                   // vtable+0x14
+	virtual MxLong Close() = 0;                         // vtable+0x18
+	virtual MxResult ReadToBuffer(MxDSBuffer* p_buffer);    // vtable+0x1c
+	virtual MxResult Read(unsigned char*, MxULong) = 0; // vtable+0x20
+	virtual MxLong Seek(MxLong, int) = 0;               // vtable+0x24
+	virtual MxULong GetBufferSize() = 0;                // vtable+0x28
+	virtual MxULong GetStreamBuffersNum() = 0;          // vtable+0x2c
+	virtual MxLong GetLengthInDWords();                 // vtable+0x30
+	virtual MxU32* GetBuffer();                         // vtable+0x34
+	inline MxLong GetPosition() const { return m_position; }
 
 protected:
 	MxULong m_lengthInDWords;
diff --git a/LEGO1/mxthread.h b/LEGO1/mxthread.h
index 3c7faab0..3695b29f 100644
--- a/LEGO1/mxthread.h
+++ b/LEGO1/mxthread.h
@@ -17,7 +17,7 @@ class MxThread {
 
 	void Terminate();
 
-	void Sleep(MxS32 p_milliseconds);
+	static void Sleep(MxS32 p_milliseconds);
 
 	// Inferred, not in DLL
 	inline MxBool IsRunning() { return m_running; }