diff --git a/lib/util/cmcd_manager.js b/lib/util/cmcd_manager.js
index ad71ea5fa4..05f75af699 100644
--- a/lib/util/cmcd_manager.js
+++ b/lib/util/cmcd_manager.js
@@ -66,6 +66,9 @@ shaka.util.CmcdManager = class {
    */
   configure(config) {
     this.config_ = config;
+    if (this.config_.sessionId && this.config_.sessionId != this.sid_) {
+      this.sid_ = '';
+    }
   }
 
   /**