diff --git a/extensions/microsoft/speech-provider.test.ts b/extensions/microsoft/speech-provider.test.ts
index 4fbf3e0729a..ce0989559f8 100644
--- a/extensions/microsoft/speech-provider.test.ts
+++ b/extensions/microsoft/speech-provider.test.ts
@@ -3,6 +3,13 @@ import os from "node:os";
 import path from "node:path";
 import type { OpenClawConfig } from "openclaw/plugin-sdk/config-runtime";
 import { afterEach, describe, expect, it, vi } from "vitest";
+
+vi.mock("node-edge-tts", () => ({
+  EdgeTTS: class {
+    async ttsPromise(): Promise<void> {}
+  },
+}));
+
 import {
   buildMicrosoftSpeechProvider,
   isCjkDominant,
diff --git a/test/vitest/vitest.extension-bluebubbles.config.ts b/test/vitest/vitest.extension-bluebubbles.config.ts
index f9931ee732f..2816e4b5369 100644
--- a/test/vitest/vitest.extension-bluebubbles.config.ts
+++ b/test/vitest/vitest.extension-bluebubbles.config.ts
@@ -17,6 +17,7 @@ export function createExtensionBlueBubblesVitestConfig(
     {
       dir: "extensions",
       env,
+      isolate: true,
       name: "extension-bluebubbles",
       passWithNoTests: true,
       setupFiles: ["test/setup.extensions.ts"],