diff --git a/src/servers/media/AddOnManager.cpp b/src/servers/media/AddOnManager.cpp
index a7c97beb02..1ebed73a21 100644
--- a/src/servers/media/AddOnManager.cpp
+++ b/src/servers/media/AddOnManager.cpp
@@ -103,9 +103,15 @@ AddOnManager::GetDecoderForFormat(xfer_entry_ref *_decoderRef,
 		|| format.type == B_MEDIA_MULTISTREAM)
 		&& format.Encoding() == 0)
 		return B_MEDIA_BAD_FORMAT;
+	if (format.type == B_MEDIA_NO_TYPE
+		|| format.type == B_MEDIA_UNKNOWN_TYPE)
+		return B_MEDIA_BAD_FORMAT;
+
 
 	BAutolock locker(fLock);
 
+	printf("AddOnManager::GetDecoderForFormat: searching decoder for encoding %ld\n", format.Encoding());
+
 	decoder_info *info;
 	for (fDecoderList.Rewind(); fDecoderList.GetNext(&info);) {
 		media_format *decoderFormat;