diff --git a/extensions/qqbot/src/engine/utils/audio.test.ts b/extensions/qqbot/src/engine/utils/audio.test.ts
index 03792b6d12e..8f1e281e150 100644
--- a/extensions/qqbot/src/engine/utils/audio.test.ts
+++ b/extensions/qqbot/src/engine/utils/audio.test.ts
@@ -197,10 +197,9 @@ describe("engine/utils/audio", () => {
       const pcm = Buffer.from([0x01, 0x00, 0x02, 0x00]);
       const wav = buildMinimalWav(pcm, 24000, 1);
       const result = parseWavFallback(wav);
-      expect(result).not.toBeNull();
-      expect(result!.length).toBe(4);
-      expect(result![0]).toBe(0x01);
-      expect(result![1]).toBe(0x00);
+      expect(result?.length).toBe(4);
+      expect(result?.[0]).toBe(0x01);
+      expect(result?.[1]).toBe(0x00);
     });
 
     it("returns null for buffers shorter than 44 bytes", () => {
@@ -243,8 +242,7 @@ describe("engine/utils/audio", () => {
       const pcm48k = Buffer.alloc(8);
       const wav = buildMinimalWav(pcm48k, 48000, 1);
       const result = parseWavFallback(wav);
-      expect(result).not.toBeNull();
-      expect(result!.length).toBe(4); // 2 samples × 2 bytes
+      expect(result?.length).toBe(4); // 2 samples × 2 bytes
     });
   });
 });