diff --git a/reactos/dll/cpl/mmsys/CMakeLists.txt b/reactos/dll/cpl/mmsys/CMakeLists.txt
index 5206561480f..62d6a5ec381 100644
--- a/reactos/dll/cpl/mmsys/CMakeLists.txt
+++ b/reactos/dll/cpl/mmsys/CMakeLists.txt
@@ -29,4 +29,5 @@ add_importlibs(mmsys
     ntdll
     kernel32)
 
+add_pch(mmsys mmsys.h)
 add_cd_file(TARGET mmsys DESTINATION reactos/system32 FOR all)
diff --git a/reactos/dll/cpl/mmsys/audio.c b/reactos/dll/cpl/mmsys/audio.c
index 129004987ba..775d94282e0 100644
--- a/reactos/dll/cpl/mmsys/audio.c
+++ b/reactos/dll/cpl/mmsys/audio.c
@@ -8,14 +8,7 @@
  *                  Dmitry Chapyshev <dmitry@reactos.org>
  */
 
-#include <windows.h>
-#include <commctrl.h>
-#include <cpl.h>
-#include <tchar.h>
-#include <stdio.h>
 #include "mmsys.h"
-#include "resource.h"
-
 
 VOID
 InitAudioDlg(HWND hwnd)
diff --git a/reactos/dll/cpl/mmsys/mmsys.c b/reactos/dll/cpl/mmsys/mmsys.c
index 6e765608f5d..9b32a7ef04a 100644
--- a/reactos/dll/cpl/mmsys/mmsys.c
+++ b/reactos/dll/cpl/mmsys/mmsys.c
@@ -9,19 +9,7 @@
  *      2005/11/23  Created
  */
 
-#include <windows.h>
-#include <commctrl.h>
-#include <initguid.h>
-#include <cfgmgr32.h>
-#include <setupapi.h>
-#include <devguid.h>
-#include <cpl.h>
-#include <tchar.h>
-#include <debug.h>
-#include <shlwapi.h>
-
 #include "mmsys.h"
-#include "resource.h"
 
 typedef enum
 {
diff --git a/reactos/dll/cpl/mmsys/mmsys.h b/reactos/dll/cpl/mmsys/mmsys.h
index ed6c480a0c0..f5085cc5714 100644
--- a/reactos/dll/cpl/mmsys/mmsys.h
+++ b/reactos/dll/cpl/mmsys/mmsys.h
@@ -1,4 +1,16 @@
-#pragma once
+#include <windows.h>
+#include <commctrl.h>
+#include <cpl.h>
+#include <tchar.h>
+#include <stdio.h>
+#include <initguid.h>
+#include <cfgmgr32.h>
+#include <setupapi.h>
+#include <devguid.h>
+#include <debug.h>
+#include <shlwapi.h>
+
+#include "resource.h"
 
 //typedef LONG (CALLBACK *APPLET_PROC)(VOID);
 
diff --git a/reactos/dll/cpl/mmsys/mmsys.rbuild b/reactos/dll/cpl/mmsys/mmsys.rbuild
index 3180e2a7888..86fb7f9e808 100644
--- a/reactos/dll/cpl/mmsys/mmsys.rbuild
+++ b/reactos/dll/cpl/mmsys/mmsys.rbuild
@@ -18,4 +18,5 @@
 	<file>audio.c</file>
 	<file>voice.c</file>
 	<file>mmsys.rc</file>
+	<pch>mmsys.h</pch>
 </module>
diff --git a/reactos/dll/cpl/mmsys/sounds.c b/reactos/dll/cpl/mmsys/sounds.c
index c7ff17187a5..48ba4f4cdeb 100644
--- a/reactos/dll/cpl/mmsys/sounds.c
+++ b/reactos/dll/cpl/mmsys/sounds.c
@@ -8,15 +8,7 @@
  *                  Dmitry Chapyshev <dmitry@reactos.org>
  */
 
-#include <windows.h>
-#include <commctrl.h>
-#include <setupapi.h>
-#include <cpl.h>
-#include <tchar.h>
-#include <stdio.h>
 #include "mmsys.h"
-#include "resource.h"
-#include <debug.h>
 
 struct __APP_MAP__;
 
diff --git a/reactos/dll/cpl/mmsys/voice.c b/reactos/dll/cpl/mmsys/voice.c
index ac5c4497111..f19fe69438c 100644
--- a/reactos/dll/cpl/mmsys/voice.c
+++ b/reactos/dll/cpl/mmsys/voice.c
@@ -8,13 +8,7 @@
  *                  Dmitry Chapyshev <dmitry@reactos.org>
  */
 
-#include <windows.h>
-#include <commctrl.h>
-#include <cpl.h>
-#include <tchar.h>
-#include <stdio.h>
 #include "mmsys.h"
-#include "resource.h"
 
 /* Voice property page dialog callback */
 INT_PTR CALLBACK
diff --git a/reactos/dll/cpl/mmsys/volume.c b/reactos/dll/cpl/mmsys/volume.c
index 19f518bccea..836b13d4596 100644
--- a/reactos/dll/cpl/mmsys/volume.c
+++ b/reactos/dll/cpl/mmsys/volume.c
@@ -8,14 +8,7 @@
  *                  Dmitry Chapyshev <dmitry@reactos.org>
  */
 
-#include <windows.h>
-#include <commctrl.h>
-#include <setupapi.h>
-#include <cpl.h>
-#include <tchar.h>
-#include <stdio.h>
 #include "mmsys.h"
-#include "resource.h"
 
 #define VOLUME_DIVIDER 0xFFF