diff --git a/src/core/mpris.h b/src/core/mpris.h
index 9010935a3..ea88274fb 100644
--- a/src/core/mpris.h
+++ b/src/core/mpris.h
@@ -79,7 +79,7 @@ class Mpris1 : public QObject {
   Q_OBJECT
 
 public:
-  Mpris1(Player* player, ArtLoader* art_loader, QObject* parent);
+  Mpris1(Player* player, ArtLoader* art_loader, QObject* parent = 0);
 
   static QVariantMap GetMetadata(const Song& song);
 
diff --git a/src/core/mpris2.h b/src/core/mpris2.h
index 298a7e3c4..66e851ffc 100644
--- a/src/core/mpris2.h
+++ b/src/core/mpris2.h
@@ -72,9 +72,7 @@ class Mpris2 : public QObject {
   Q_PROPERTY( bool CanEditTracks READ CanEditTracks )
 
 public:
-  Mpris2(Player* player, ArtLoader* art_loader,
-         Mpris1* mpris1, QObject* parent);
-
+  Mpris2(Player* player, ArtLoader* art_loader, Mpris1* mpris1, QObject* parent = 0); 
   // Root Properties
   bool CanQuit() const;
   bool CanRaise() const;
diff --git a/src/core/mpris_common.h b/src/core/mpris_common.h
index bfdfe3b2d..e37d642a8 100644
--- a/src/core/mpris_common.h
+++ b/src/core/mpris_common.h
@@ -39,7 +39,7 @@ class ArtLoader : public QObject {
   Q_OBJECT
 
 public:
-  ArtLoader(QObject* parent);
+  ArtLoader(QObject* parent = 0);
   ~ArtLoader();
 
 public slots: