diff --git a/reactos/drivers/multimedia/directory.rbuild b/reactos/drivers/multimedia/directory.rbuild
index aeca33a8b78..416519a9e84 100755
--- a/reactos/drivers/multimedia/directory.rbuild
+++ b/reactos/drivers/multimedia/directory.rbuild
@@ -16,9 +16,9 @@
 	<xi:include href="drmk/drmk.rbuild" />
 </directory>
 
-<directory name="portcls">
+<!--<directory name="portcls">
 	<xi:include href="portcls/portcls.rbuild" />
-</directory>
+</directory>-->
 
 <!--<directory name="avtest">
 	<xi:include href="avtest/avtest.rbuild" />
@@ -29,9 +29,9 @@
 	Drivers (experimental)
 -->
 
-<directory name="mpu401_ks">
+<!--<directory name="mpu401_ks">
 	<xi:include href="mpu401_ks/mpu401.rbuild" />
-</directory>
+</directory>-->
 
 <directory name="sb16_nt4">
 	<xi:include href="sb16_nt4/sb16_nt4.rbuild" />
diff --git a/reactos/drivers/multimedia/portcls/portcls.rbuild b/reactos/drivers/multimedia/portcls/portcls.rbuild
index fdf5c4c356a..04666a1241d 100644
--- a/reactos/drivers/multimedia/portcls/portcls.rbuild
+++ b/reactos/drivers/multimedia/portcls/portcls.rbuild
@@ -15,7 +15,7 @@
     <file>stubs.c</file>
 
     <!-- Probably not the best idea to have this separate -->
-    <file>../stdunk/stdunk.c</file>
+    <!--<file>../stdunk/stdunk.c</file>-->
 
     <file>helper/ResourceList.c</file>
 
diff --git a/reactos/include/ddk/ks.h b/reactos/include/ddk/ks.h
index e0dd7e73190..3d9ad50839d 100644
--- a/reactos/include/ddk/ks.h
+++ b/reactos/include/ddk/ks.h
@@ -1905,7 +1905,7 @@ KsAddObjectCreateItemToObjectHeader(
 
 KSDDKAPI NTSTATUS NTAPI
 KsAllocateDeviceHeader(
-    OUT PVOID Header,
+    OUT KSDEVICE_HEADER* Header,
     IN  ULONG ItemsCount,
     IN  PKSOBJECT_CREATE_ITEM ItemsList OPTIONAL);
 
diff --git a/reactos/include/ddk/portcls.h b/reactos/include/ddk/portcls.h
index 8bf0d5dfb56..c0eb730b564 100644
--- a/reactos/include/ddk/portcls.h
+++ b/reactos/include/ddk/portcls.h
@@ -135,7 +135,7 @@
 /* HACK */
 typedef PVOID CM_RESOURCE_TYPE;
 
-
+#define PORT_CLASS_DEVICE_EXTENSION_SIZE (64 * sizeof(ULONG_PTR))
 
 /* ===============================================================
     Class IDs - TODO