diff --git a/src/add-ons/media/media-add-ons/opensound/OpenSoundAddOn.h b/src/add-ons/media/media-add-ons/opensound/OpenSoundAddOn.h
index 998f26dd32..b579e4581d 100644
--- a/src/add-ons/media/media-add-ons/opensound/OpenSoundAddOn.h
+++ b/src/add-ons/media/media-add-ons/opensound/OpenSoundAddOn.h
@@ -17,6 +17,8 @@
 
 #define SETTINGS_FILE					"Media/oss_audio_settings"
 
+class BEntry;
+
 class OpenSoundAddOn :
 	public BMediaAddOn
 {
diff --git a/src/add-ons/media/media-add-ons/opensound/OpenSoundNode.h b/src/add-ons/media/media-add-ons/opensound/OpenSoundNode.h
index 17f2678329..05dc37067d 100644
--- a/src/add-ons/media/media-add-ons/opensound/OpenSoundNode.h
+++ b/src/add-ons/media/media-add-ons/opensound/OpenSoundNode.h
@@ -23,7 +23,7 @@ class OpenSoundDeviceEngine;
 class OpenSoundDeviceMixer;
 
 struct audio_buf_info;
-
+struct flavor_info;
 
 class OpenSoundNode : public BBufferConsumer, public BBufferProducer,
 	public BTimeSource, public BMediaEventLooper, public BControllable {