diff --git a/reactos/drivers/wdm/audio/backpln/portcls/interfaces.hpp b/reactos/drivers/wdm/audio/backpln/portcls/interfaces.hpp
index 01695ba3804..53c41d55ff0 100644
--- a/reactos/drivers/wdm/audio/backpln/portcls/interfaces.hpp
+++ b/reactos/drivers/wdm/audio/backpln/portcls/interfaces.hpp
@@ -970,7 +970,7 @@ DECLARE_INTERFACE_(IDmaChannelInit, IUnknown)
 {
     DEFINE_ABSTRACT_UNKNOWN()
     DEFINE_ABSTRACT_DMACHANNEL_EX()
-    //DEFINE_ABSTRACT_DMACHANNELSLAVE()
+    DEFINE_ABSTRACT_DMACHANNELSLAVE()
 
     STDMETHOD_(NTSTATUS, Init)( THIS_
         IN PDEVICE_DESCRIPTION DeviceDescription,