diff --git a/web/app/assets/javascripts/session.js b/web/app/assets/javascripts/session.js
index 06d7ab3b2..1bdb38990 100644
--- a/web/app/assets/javascripts/session.js
+++ b/web/app/assets/javascripts/session.js
@@ -1464,7 +1464,10 @@
 
             // make sure no previous plays are still going on by accident
             context.jamClient.SessionStopPlay();
-            context.jamClient.SessionRemoveAllPlayTracks();
+            if(context.jamClient.SessionRemoveAllPlayTracks) {
+              // upgrade guard
+              context.jamClient.SessionRemoveAllPlayTracks();
+            }
         };