Add debug logs for state changes on sink
diff --git a/audio/sink.c b/audio/sink.c
index cb3ca74..770eae3 100644
--- a/audio/sink.c
+++ b/audio/sink.c
@@ -80,6 +80,13 @@
 
 static unsigned int avdtp_callback_id = 0;
 
+static char *str_state[] = {
+	"SINK_STATE_DISCONNECTED",
+	"SINK_STATE_CONNECTING",
+	"SINK_STATE_CONNECTED",
+	"SINK_STATE_PLAYING",
+};
+
 static const char *state2str(sink_state_t state)
 {
 	switch (state) {
@@ -112,6 +119,9 @@
 					AUDIO_SINK_INTERFACE, "State",
 					DBUS_TYPE_STRING, &state_str);
 
+	DBG("State changed %s: %s -> %s", dev->path, str_state[old_state],
+		str_state[new_state]);
+
 	for (l = sink_callbacks; l != NULL; l = l->next) {
 		struct sink_state_callback *cb = l->data;
 		cb->cb(dev, old_state, new_state, cb->user_data);