diff --git a/src/event/MaskMonitor.cxx b/src/event/MaskMonitor.cxx
index c22ba36e2..d69329b1d 100644
--- a/src/event/MaskMonitor.cxx
+++ b/src/event/MaskMonitor.cxx
@@ -24,11 +24,11 @@ void
 MaskMonitor::OrMask(unsigned new_mask)
 {
 	if (pending_mask.fetch_or(new_mask) == 0)
-		DeferredMonitor::Schedule();
+		defer.Schedule();
 }
 
 void
-MaskMonitor::RunDeferred()
+MaskMonitor::RunDeferred() noexcept
 {
 	const unsigned mask = pending_mask.exchange(0);
 	if (mask != 0)
diff --git a/src/event/MaskMonitor.hxx b/src/event/MaskMonitor.hxx
index a754c4a81..5f2352983 100644
--- a/src/event/MaskMonitor.hxx
+++ b/src/event/MaskMonitor.hxx
@@ -21,7 +21,7 @@
 #define MPD_EVENT_MASK_MONITOR_HXX
 
 #include "check.h"
-#include "DeferredMonitor.hxx"
+#include "DeferEvent.hxx"
 #include "util/BindMethod.hxx"
 
 #include <atomic>
@@ -32,7 +32,9 @@
  *
  * This class is thread-safe.
  */
-class MaskMonitor final : DeferredMonitor {
+class MaskMonitor final {
+	DeferEvent defer;
+
 	typedef BoundMethod<void(unsigned)> Callback;
 	const Callback callback;
 
@@ -40,16 +42,22 @@ class MaskMonitor final : DeferredMonitor {
 
 public:
 	MaskMonitor(EventLoop &_loop, Callback _callback)
-		:DeferredMonitor(_loop), callback(_callback), pending_mask(0) {}
+		:defer(_loop, BIND_THIS_METHOD(RunDeferred)),
+		 callback(_callback), pending_mask(0) {}
 
-	using DeferredMonitor::GetEventLoop;
-	using DeferredMonitor::Cancel;
+	EventLoop &GetEventLoop() {
+		return defer.GetEventLoop();
+	}
+
+	void Cancel() {
+		defer.Cancel();
+	}
 
 	void OrMask(unsigned new_mask);
 
 protected:
-	/* virtual methode from class DeferredMonitor */
-	void RunDeferred() override;
+	/* DeferEvent callback */
+	void RunDeferred() noexcept;
 };
 
 #endif