diff --git a/layout/reftests/webm-video/bug686957.html b/layout/reftests/webm-video/bug686957.html
index fe541b13dfb..59b6f1596fd 100644
--- a/layout/reftests/webm-video/bug686957.html
+++ b/layout/reftests/webm-video/bug686957.html
@@ -12,7 +12,7 @@
        preload="auto"
        id="v"
        onloadedmetadata="document.getElementById('v').currentTime=document.getElementById('v').duration"
-       onseeked="setTimeout(function(){document.documentElement.className = '';}, 15);"
+       onseeked="setTimeout(function(){document.documentElement.className = '';}, 100);"
 </video>
 </body>
 </html>