diff --git a/src/message-transport.ts b/src/message-transport.ts
index 9e4d49d..0b53d9a 100644
--- a/src/message-transport.ts
+++ b/src/message-transport.ts
@@ -75,7 +75,7 @@ export class PostMessageTransport implements Transport {
   ) {
     this.messageListener = (event) => {
       if (eventSource && event.source !== this.eventSource) {
-        console.error("Ignoring message from unknown source", event);
+        console.debug("Ignoring message from unknown source", event);
         return;
       }
       const parsed = JSONRPCMessageSchema.safeParse(event.data);