diff --git a/dll/win32/mmdevapi/devenum.c b/dll/win32/mmdevapi/devenum.c
index b189e8e060b..685ec27de62 100644
--- a/dll/win32/mmdevapi/devenum.c
+++ b/dll/win32/mmdevapi/devenum.c
@@ -338,7 +338,7 @@ static MMDevice *MMDevice_Create(WCHAR *name, GUID *id, EDataFlow flow, DWORD st
     cur->state = state;
     cur->devguid = *id;
 
-    StringFromGUID2(&cur->devguid, guidstr, sizeof(guidstr)/sizeof(*guidstr));
+    StringFromGUID2(&cur->devguid, guidstr, ARRAY_SIZE(guidstr));
 
     if (flow == eRender)
         root = key_render;
@@ -429,7 +429,7 @@ static HRESULT load_devices_from_reg(void)
         DWORD len;
         PROPVARIANT pv = { VT_EMPTY };
 
-        len = sizeof(guidvalue)/sizeof(guidvalue[0]);
+        len = ARRAY_SIZE(guidvalue);
         ret = RegEnumKeyExW(cur, i++, guidvalue, &len, NULL, NULL, NULL, NULL);
         if (ret == ERROR_NO_MORE_ITEMS)
         {
@@ -1395,7 +1395,7 @@ static HRESULT WINAPI MMDevPropStore_GetCount(IPropertyStore *iface, DWORD *npro
         return hr;
     *nprops = 0;
     do {
-        DWORD len = sizeof(buffer)/sizeof(*buffer);
+        DWORD len = ARRAY_SIZE(buffer);
         if (RegEnumValueW(propkey, i, buffer, &len, NULL, NULL, NULL, NULL) != ERROR_SUCCESS)
             break;
         i++;
@@ -1410,7 +1410,7 @@ static HRESULT WINAPI MMDevPropStore_GetAt(IPropertyStore *iface, DWORD prop, PR
 {
     MMDevPropStore *This = impl_from_IPropertyStore(iface);
     WCHAR buffer[50];
-    DWORD len = sizeof(buffer)/sizeof(*buffer);
+    DWORD len = ARRAY_SIZE(buffer);
     HRESULT hr;
     HKEY propkey;
 
@@ -1530,7 +1530,7 @@ static HRESULT WINAPI PB_Read(IPropertyBag *iface, LPCOLESTR name, VARIANT *var,
     if (!lstrcmpW(name, dsguid))
     {
         WCHAR guidstr[39];
-        StringFromGUID2(&This->devguid, guidstr,sizeof(guidstr)/sizeof(*guidstr));
+        StringFromGUID2(&This->devguid, guidstr,ARRAY_SIZE(guidstr));
         var->n1.n2.vt = VT_BSTR;
         var->n1.n2.n3.bstrVal = SysAllocString(guidstr);
         return S_OK;
diff --git a/dll/win32/mmdevapi/main.c b/dll/win32/mmdevapi/main.c
index 2b0a6f946bd..8886975c96a 100644
--- a/dll/win32/mmdevapi/main.c
+++ b/dll/win32/mmdevapi/main.c
@@ -295,7 +295,7 @@ HRESULT WINAPI DllGetClassObject(REFCLSID rclsid, REFIID riid, LPVOID *ppv)
         return E_NOINTERFACE;
     }
 
-    for (i = 0; i < sizeof(MMDEVAPI_CF)/sizeof(MMDEVAPI_CF[0]); ++i)
+    for (i = 0; i < ARRAY_SIZE(MMDEVAPI_CF); ++i)
     {
         if (IsEqualGUID(rclsid, MMDEVAPI_CF[i].rclsid)) {
             IClassFactory_AddRef(&MMDEVAPI_CF[i].IClassFactory_iface);
diff --git a/media/doc/README.WINE b/media/doc/README.WINE
index 25458c0b00f..bb6ca8c70a0 100644
--- a/media/doc/README.WINE
+++ b/media/doc/README.WINE
@@ -97,7 +97,7 @@ reactos/dll/win32/mciseq              # Synced to WineStaging-3.3
 reactos/dll/win32/mciwave             # Synced to WineStaging-4.0
 reactos/dll/win32/mgmtapi             # Synced to WineStaging-3.3
 reactos/dll/win32/mlang               # Synced to WineStaging-4.0
-reactos/dll/win32/mmdevapi            # Synced to WineStaging-3.3
+reactos/dll/win32/mmdevapi            # Synced to WineStaging-4.0
 reactos/dll/win32/mpr                 # Synced to WineStaging-3.17
 reactos/dll/win32/mprapi              # Synced to WineStaging-3.3
 reactos/dll/win32/msacm32             # Synced to WineStaging-3.3