diff --git a/src/media-understanding/runner.auto-audio.test.ts b/src/media-understanding/runner.auto-audio.test.ts
index b01291c8831..e1c4b25c43a 100644
--- a/src/media-understanding/runner.auto-audio.test.ts
+++ b/src/media-understanding/runner.auto-audio.test.ts
@@ -1,41 +1,7 @@
-import fs from "node:fs/promises";
-import os from "node:os";
-import path from "node:path";
 import { describe, expect, it } from "vitest";
-import type { MsgContext } from "../auto-reply/templating.js";
 import type { OpenClawConfig } from "../config/config.js";
-import {
-  buildProviderRegistry,
-  createMediaAttachmentCache,
-  normalizeMediaAttachments,
-  runCapability,
-} from "./runner.js";
-
-async function withAudioFixture(
-  run: (params: {
-    ctx: MsgContext;
-    media: ReturnType<typeof normalizeMediaAttachments>;
-    cache: ReturnType<typeof createMediaAttachmentCache>;
-  }) => Promise<void>,
-) {
-  const originalPath = process.env.PATH;
-  process.env.PATH = "";
-  const tmpPath = path.join(os.tmpdir(), `openclaw-auto-audio-${Date.now()}.wav`);
-  await fs.writeFile(tmpPath, Buffer.from("RIFF"));
-  const ctx: MsgContext = { MediaPath: tmpPath, MediaType: "audio/wav" };
-  const media = normalizeMediaAttachments(ctx);
-  const cache = createMediaAttachmentCache(media, {
-    localPathRoots: [path.dirname(tmpPath)],
-  });
-
-  try {
-    await run({ ctx, media, cache });
-  } finally {
-    process.env.PATH = originalPath;
-    await cache.cleanup();
-    await fs.unlink(tmpPath).catch(() => {});
-  }
-}
+import { buildProviderRegistry, runCapability } from "./runner.js";
+import { withAudioFixture } from "./runner.test-utils.js";
 
 function createOpenAiAudioProvider(
   transcribeAudio: (req: { model?: string }) => Promise<{ text: string; model: string }>,
@@ -65,7 +31,7 @@ function createOpenAiAudioCfg(extra?: Partial<OpenClawConfig>): OpenClawConfig {
 
 describe("runCapability auto audio entries", () => {
   it("uses provider keys to auto-enable audio transcription", async () => {
-    await withAudioFixture(async ({ ctx, media, cache }) => {
+    await withAudioFixture("openclaw-auto-audio", async ({ ctx, media, cache }) => {
       let seenModel: string | undefined;
       const providerRegistry = createOpenAiAudioProvider(async (req) => {
         seenModel = req.model;
@@ -88,7 +54,7 @@ describe("runCapability auto audio entries", () => {
   });
 
   it("skips auto audio when disabled", async () => {
-    await withAudioFixture(async ({ ctx, media, cache }) => {
+    await withAudioFixture("openclaw-auto-audio", async ({ ctx, media, cache }) => {
       const providerRegistry = createOpenAiAudioProvider(async () => ({
         text: "ok",
         model: "whisper-1",
@@ -117,7 +83,7 @@ describe("runCapability auto audio entries", () => {
   });
 
   it("prefers explicitly configured audio model entries", async () => {
-    await withAudioFixture(async ({ ctx, media, cache }) => {
+    await withAudioFixture("openclaw-auto-audio", async ({ ctx, media, cache }) => {
       let seenModel: string | undefined;
       const providerRegistry = createOpenAiAudioProvider(async (req) => {
         seenModel = req.model;
diff --git a/src/media-understanding/runner.deepgram.test.ts b/src/media-understanding/runner.deepgram.test.ts
index e4c42d0e64a..38df19b7432 100644
--- a/src/media-understanding/runner.deepgram.test.ts
+++ b/src/media-understanding/runner.deepgram.test.ts
@@ -1,45 +1,11 @@
-import fs from "node:fs/promises";
-import os from "node:os";
-import path from "node:path";
 import { describe, expect, it } from "vitest";
-import type { MsgContext } from "../auto-reply/templating.js";
 import type { OpenClawConfig } from "../config/config.js";
-import {
-  buildProviderRegistry,
-  createMediaAttachmentCache,
-  normalizeMediaAttachments,
-  runCapability,
-} from "./runner.js";
-
-async function withAudioFixture(
-  run: (params: {
-    ctx: MsgContext;
-    media: ReturnType<typeof normalizeMediaAttachments>;
-    cache: ReturnType<typeof createMediaAttachmentCache>;
-  }) => Promise<void>,
-) {
-  const originalPath = process.env.PATH;
-  process.env.PATH = "";
-  const tmpPath = path.join(os.tmpdir(), `openclaw-deepgram-${Date.now()}.wav`);
-  await fs.writeFile(tmpPath, Buffer.from("RIFF"));
-  const ctx: MsgContext = { MediaPath: tmpPath, MediaType: "audio/wav" };
-  const media = normalizeMediaAttachments(ctx);
-  const cache = createMediaAttachmentCache(media, {
-    localPathRoots: [path.dirname(tmpPath)],
-  });
-
-  try {
-    await run({ ctx, media, cache });
-  } finally {
-    process.env.PATH = originalPath;
-    await cache.cleanup();
-    await fs.unlink(tmpPath).catch(() => {});
-  }
-}
+import { buildProviderRegistry, runCapability } from "./runner.js";
+import { withAudioFixture } from "./runner.test-utils.js";
 
 describe("runCapability deepgram provider options", () => {
   it("merges provider options, headers, and baseUrl overrides", async () => {
-    await withAudioFixture(async ({ ctx, media, cache }) => {
+    await withAudioFixture("openclaw-deepgram", async ({ ctx, media, cache }) => {
       let seenQuery: Record<string, string | number | boolean> | undefined;
       let seenBaseUrl: string | undefined;
       let seenHeaders: Record<string, string> | undefined;
diff --git a/src/media-understanding/runner.test-utils.ts b/src/media-understanding/runner.test-utils.ts
new file mode 100644
index 00000000000..823d63ea943
--- /dev/null
+++ b/src/media-understanding/runner.test-utils.ts
@@ -0,0 +1,34 @@
+import fs from "node:fs/promises";
+import os from "node:os";
+import path from "node:path";
+import type { MsgContext } from "../auto-reply/templating.js";
+import { withEnvAsync } from "../test-utils/env.js";
+import { createMediaAttachmentCache, normalizeMediaAttachments } from "./runner.js";
+
+type AudioFixtureParams = {
+  ctx: MsgContext;
+  media: ReturnType<typeof normalizeMediaAttachments>;
+  cache: ReturnType<typeof createMediaAttachmentCache>;
+};
+
+export async function withAudioFixture(
+  filePrefix: string,
+  run: (params: AudioFixtureParams) => Promise<void>,
+) {
+  const tmpPath = path.join(os.tmpdir(), `${filePrefix}-${Date.now()}.wav`);
+  await fs.writeFile(tmpPath, Buffer.from("RIFF"));
+  const ctx: MsgContext = { MediaPath: tmpPath, MediaType: "audio/wav" };
+  const media = normalizeMediaAttachments(ctx);
+  const cache = createMediaAttachmentCache(media, {
+    localPathRoots: [path.dirname(tmpPath)],
+  });
+
+  try {
+    await withEnvAsync({ PATH: "" }, async () => {
+      await run({ ctx, media, cache });
+    });
+  } finally {
+    await cache.cleanup();
+    await fs.unlink(tmpPath).catch(() => {});
+  }
+}