diff --git a/src/multimedia/audio/qaudio.h b/src/multimedia/audio/qaudio.h
index f2cd9e6b..c93e29e7 100644
--- a/src/multimedia/audio/qaudio.h
+++ b/src/multimedia/audio/qaudio.h
@@ -56,6 +56,8 @@ QT_MODULE(Multimedia)
 
 //QTM_SYNC_HEADER_EXPORT QAudio
 
+// Class forward declaration required for QDoc bug
+class QString;
 namespace QAudio
 {
     enum Error { NoError, OpenError, IOError, UnderrunError, FatalError };
diff --git a/src/multimedia/playback/qaudioendpointselector.h b/src/multimedia/playback/qaudioendpointselector.h
index 85e1ae65..97c9f00a 100644
--- a/src/multimedia/playback/qaudioendpointselector.h
+++ b/src/multimedia/playback/qaudioendpointselector.h
@@ -52,6 +52,8 @@ QT_BEGIN_NAMESPACE
 QT_MODULE(Multimedia)
 
 
+// Class forward declaration required for QDoc bug
+class QString;
 class Q_MULTIMEDIA_EXPORT QAudioEndpointSelector : public QMediaControl
 {
     Q_OBJECT
diff --git a/src/multimedia/playback/qmediaresource.h b/src/multimedia/playback/qmediaresource.h
index 4fe8a0c0..7de83ce6 100644
--- a/src/multimedia/playback/qmediaresource.h
+++ b/src/multimedia/playback/qmediaresource.h
@@ -54,7 +54,8 @@ QT_BEGIN_NAMESPACE
 
 QT_MODULE(Multimedia)
 
-
+// Class forward declaration required for QDoc bug
+class QString;
 class Q_MULTIMEDIA_EXPORT QMediaResource
 {
 public:
diff --git a/src/multimedia/qtmedianamespace.h b/src/multimedia/qtmedianamespace.h
index a206720e..2f0f423b 100644
--- a/src/multimedia/qtmedianamespace.h
+++ b/src/multimedia/qtmedianamespace.h
@@ -54,6 +54,9 @@ QT_BEGIN_NAMESPACE
 
 QT_MODULE(Multimedia)
 
+// Class forward declaration required for QDoc bug
+class QString;
+
 #define Q_DECLARE_METADATA(key) Q_MULTIMEDIA_EXPORT extern const QString key
 
 namespace QtMultimedia