From 83a62bcc5398d4589e6b5ef55435dcca78bd9f51 Mon Sep 17 00:00:00 2001
From: ANDROIDHASSAN <84630851+ANDROIDHASSAN@users.noreply.github.com>
Date: Thu, 12 Nov 2026 20:07:12 +0530
Subject: [PATCH 1/2] fix(rtc-node): return no frames from
 AudioResampler.flush() when nothing is buffered

The FFI flush response carries a non-zero outputPtr with size 0 when the resampler has nothing left, so the pointer check never matched and flush() returned one 0-sample frame. Check the size instead.
---
 .changeset/resampler-flush-empty.md            |  5 +++++
 .../livekit-rtc/src/audio_resampler.test.ts    | 18 ++++++++++++++++++
 packages/livekit-rtc/src/audio_resampler.ts    |  2 +-
 3 files changed, 24 insertions(+), 1 deletion(-)
 create mode 100644 .changeset/resampler-flush-empty.md
 create mode 100644 packages/livekit-rtc/src/audio_resampler.test.ts

diff --git a/.changeset/resampler-flush-empty.md b/.changeset/resampler-flush-empty.md
new file mode 100644
index 00000000..9b72dff8
--- /dev/null
+++ b/.changeset/resampler-flush-empty.md
@@ -0,0 +1,5 @@
+---
+'@livekit/rtc-node': patch
+---
+
+Return no frames from `AudioResampler.flush()` when nothing is buffered, instead of one empty frame.
diff --git a/packages/livekit-rtc/src/audio_resampler.test.ts b/packages/livekit-rtc/src/audio_resampler.test.ts
new file mode 100644
index 00000000..1b9642fa
--- /dev/null
+++ b/packages/livekit-rtc/src/audio_resampler.test.ts
@@ -0,0 +1,18 @@
+// SPDX-FileCopyrightText: 2026 LiveKit, Inc.
+//
+// SPDX-License-Identifier: Apache-2.0
+import { describe, expect, it } from 'vitest';
+import { AudioFrame } from './audio_frame.js';
+import { AudioResampler } from './audio_resampler.js';
+
+describe('AudioResampler', () => {
+  it('flush returns no frames when nothing is buffered', () => {
+    const resampler = new AudioResampler(48000, 16000);
+    expect(resampler.flush()).toEqual([]);
+
+    resampler.push(new AudioFrame(new Int16Array(4800), 48000, 1, 4800));
+    const tail = resampler.flush();
+    expect(tail.reduce((n, f) => n + f.samplesPerChannel, 0)).toBeGreaterThan(0);
+    expect(resampler.flush()).toEqual([]);
+  });
+});
diff --git a/packages/livekit-rtc/src/audio_resampler.ts b/packages/livekit-rtc/src/audio_resampler.ts
index 24bb0ec1..5da7b321 100644
--- a/packages/livekit-rtc/src/audio_resampler.ts
+++ b/packages/livekit-rtc/src/audio_resampler.ts
@@ -174,7 +174,7 @@ export class AudioResampler {
       throw new Error(res.error);
     }
 
-    if (!res.outputPtr) {
+    if (!res.size) {
       return [];
     }
 

From 25a85e26ab4aace39b860c35189b255b204079b4 Mon Sep 17 00:00:00 2001
From: ANDROIDHASSAN <84630851+ANDROIDHASSAN@users.noreply.github.com>
Date: Thu, 12 Nov 2026 20:14:40 +0530
Subject: [PATCH 2/2] fix(rtc-node): keep the output pointer guard so the dts
 build narrows it

---
 packages/livekit-rtc/src/audio_resampler.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/livekit-rtc/src/audio_resampler.ts b/packages/livekit-rtc/src/audio_resampler.ts
index 5da7b321..080e876e 100644
--- a/packages/livekit-rtc/src/audio_resampler.ts
+++ b/packages/livekit-rtc/src/audio_resampler.ts
@@ -174,7 +174,7 @@ export class AudioResampler {
       throw new Error(res.error);
     }
 
-    if (!res.size) {
+    if (!res.outputPtr || !res.size) {
       return [];
     }