diff --git a/src/extensions/core/uploadAudio.ts b/src/extensions/core/uploadAudio.ts
index bde5af6c1f..d6bec005a2 100644
--- a/src/extensions/core/uploadAudio.ts
+++ b/src/extensions/core/uploadAudio.ts
@@ -178,8 +178,9 @@ app.registerExtension({
         audioUIWidget.options.canvasOnly = true
 
         const onAudioWidgetUpdate = () => {
+          if (typeof audioWidget.value !== 'string') return
           audioUIWidget.element.src = api.apiURL(
-            getResourceURL(...splitFilePath(audioWidget.value as string))
+            getResourceURL(...splitFilePath(audioWidget.value))
           )
         }
         // Initially load default audio file to audioUIWidget.