diff --git a/src/public/js/components/buttons/download.js b/src/public/js/components/buttons/download.js
index 89ce699..dfcc217 100644
--- a/src/public/js/components/buttons/download.js
+++ b/src/public/js/components/buttons/download.js
@@ -71,11 +71,13 @@ class Player extends React.PureComponent {
     super(props);
   }
   render() {
+    const subtitles = this.props.subtitles;
+    const hasSubtitles = (subtitles !== undefined && subtitles !== null);
     return (
       <div className="embed-responsive embed-responsive-16by9">
         <video controls>
           <source src={this.props.url} type="video/mp4"/>
-          {this.props.subtitles !== undefined && this.props.subtitles.toIndexedSeq().map(function(el, index) {
+          {hasSubtitles && subtitles.toIndexedSeq().map(function(el, index) {
             return (
               <track
                 key={index}