diff --git a/src/demux/transmuxer-worker.ts b/src/demux/transmuxer-worker.ts
index 53a9d131d7a..91af57de223 100644
--- a/src/demux/transmuxer-worker.ts
+++ b/src/demux/transmuxer-worker.ts
@@ -30,8 +30,12 @@ function startWorker() {
     if (data.cmd === 'init') {
       const config = JSON.parse(data.config);
       const observer = new EventEmitter();
-      observer.on(Events.FRAG_DECRYPTED, forwardMessage);
-      observer.on(Events.ERROR, forwardMessage);
+      observer.on(Events.FRAG_DECRYPTED, (event, data) =>
+        forwardMessage(event, data, instanceNo),
+      );
+      observer.on(Events.ERROR, (event, data) =>
+        forwardMessage(event, data, instanceNo),
+      );
       const logger = enableLogs(config.debug, data.id);
       forwardWorkerLogs(logger, instanceNo);
       transmuxers[instanceNo] = new Transmuxer(
diff --git a/src/demux/transmuxer.ts b/src/demux/transmuxer.ts
index bf88f7a6a34..2d1168e2a85 100644
--- a/src/demux/transmuxer.ts
+++ b/src/demux/transmuxer.ts
@@ -363,6 +363,9 @@ export default class Transmuxer {
       this.remuxer.destroy();
       this.remuxer = undefined;
     }
+    if (this.observer) {
+      this.observer.removeAllListeners();
+    }
     this.decryptionPromise = null;
     this.decrypter = this.observer = undefined;
     //@ts-ignore