Index: uspace/srv/audio/hound/audio_source.h
===================================================================
--- uspace/srv/audio/hound/audio_source.h	(revision 4eff63c6227688ae1de2299f2c9c78d7b2618abf)
+++ uspace/srv/audio/hound/audio_source.h	(revision e211ea04fccf33d4cb2092f630a29e893e096a02)
@@ -55,7 +55,7 @@
 	void *private_data;
 	/** Callback for connection and disconnection */
-	int (*connection_change)(audio_source_t *source, bool added);
+	errno_t (*connection_change)(audio_source_t *source, bool added);
 	/** Ask backend for more data */
-	int (*update_available_data)(audio_source_t *source, size_t size);
+	errno_t (*update_available_data)(audio_source_t *source, size_t size);
 };
 
@@ -70,10 +70,10 @@
 }
 
-int audio_source_init(audio_source_t *source, const char *name, void *data,
-    int (*connection_change)(audio_source_t *, bool),
-    int (*update_available_data)(audio_source_t *, size_t),
+errno_t audio_source_init(audio_source_t *source, const char *name, void *data,
+    errno_t (*connection_change)(audio_source_t *, bool),
+    errno_t (*update_available_data)(audio_source_t *, size_t),
     const pcm_format_t *f);
 void audio_source_fini(audio_source_t *source);
-int audio_source_push_data(audio_source_t *source, const void *data,
+errno_t audio_source_push_data(audio_source_t *source, const void *data,
     size_t size);
 static inline const pcm_format_t *audio_source_format(const audio_source_t *s)