From 8288b8b793028ef01970c9542452223429e83c72 Mon Sep 17 00:00:00 2001
From: webadderall <131426131+webadderall@users.noreply.github.com>
Date: Tue, 2 Jun 2026 11:10:45 +1000
Subject: [PATCH] fix: keep embedded audio in legacy mac mic sidecar exports

---
 src/lib/exporter/audioEncoder.test.ts | 22 ++++++++++++++++++++++
 src/lib/exporter/audioEncoder.ts      |  6 ++++++
 2 files changed, 28 insertions(+)

diff --git a/src/lib/exporter/audioEncoder.test.ts b/src/lib/exporter/audioEncoder.test.ts
index 6047b548..92a1a887 100644
--- a/src/lib/exporter/audioEncoder.test.ts
+++ b/src/lib/exporter/audioEncoder.test.ts
@@ -161,6 +161,28 @@ describe("AudioProcessor offline render preparation", () => {
 		expect(renderAndMuxOfflineAudio).toHaveBeenCalled();
 	});
 
+	it("avoids the single-sidecar fast path for legacy mac mic sidecars that still need embedded audio", async () => {
+		const processor = new AudioProcessor() as unknown as OfflineRenderTestHarness;
+		const loadAudioFileDemuxer = vi.spyOn(processor, "loadAudioFileDemuxer");
+		const renderAndMuxOfflineAudio = vi
+			.spyOn(processor, "renderAndMuxOfflineAudio")
+			.mockResolvedValue();
+
+		await processor.process(
+			{} as never,
+			{} as never,
+			"file:///tmp/recording.mp4",
+			[],
+			[],
+			undefined,
+			[],
+			["/tmp/recording.mic.m4a"],
+		);
+
+		expect(loadAudioFileDemuxer).not.toHaveBeenCalled();
+		expect(renderAndMuxOfflineAudio).toHaveBeenCalled();
+	});
+
 	it("soft-limits mixed peaks before encoding or WAV conversion", () => {
 		const samples = new Float32Array([
 			-1.6,
diff --git a/src/lib/exporter/audioEncoder.ts b/src/lib/exporter/audioEncoder.ts
index d66e0bea..6f1ca075 100644
--- a/src/lib/exporter/audioEncoder.ts
+++ b/src/lib/exporter/audioEncoder.ts
@@ -263,12 +263,18 @@ export class AudioProcessor {
 			videoUrl,
 			sortedSourceAudioFallbackPaths,
 		);
+		const requiresLegacyMacMicSidecarMix =
+			routingPolicy.includeEmbeddedInExport &&
+			!routingPolicy.hasEmbeddedSourceAudio &&
+			routingPolicy.playbackPaths.length === 1 &&
+			routingPolicy.playbackPaths[0]?.toLowerCase().endsWith(".mic.m4a") === true;
 		const hasTimedCompanionAudio = routingPolicy.playbackPaths.some(
 			(audioPath) => (sourceAudioFallbackStartDelayMsByPath?.[audioPath] ?? 0) > 0,
 		);
 		const needsSourceAudioMixing =
 			routingPolicy.playbackPaths.length > 1 ||
 			(routingPolicy.hasEmbeddedSourceAudio && routingPolicy.playbackPaths.length > 0) ||
+			requiresLegacyMacMicSidecarMix ||
 			hasTimedCompanionAudio;
 
 		// When speed edits, audio regions, or multiple audio sources need mixing, use offline AudioContext pipeline.