diff --git a/src/views/Release.jsx b/src/views/Release.jsx
index fc601bb..a6e0411 100644
--- a/src/views/Release.jsx
+++ b/src/views/Release.jsx
@@ -15,7 +15,7 @@ const Recordings = (props) => {
   let mediasComponent = <EntityList placeholder={true} size={25}/>;
   if(medias) {
     const list= medias.map((media) => ({
-      'header': media.format + ' ' + media.position,
+      'header': (media.format ? media.format : 'Desconocido') + ' - ' + media.position,
       'items': media.recordings.map((recording) => ({
         'id': recording.id,
         'link': props.makeLink(recording.id),