[BUG] Infinite export loop when adding looped background music to a silent video at 1x speed

[shahabhilash]

Bug: Infinite export when looping background music on videos without original audio

Description

If a user uploads a video that has no audio track (or mutes the original audio so hasOriginalAudio === false) and adds a background music track with “Loop Music” enabled, the export process never finishes.

The FFmpeg process continues indefinitely, eventually:

• crashing the browser tab, or
• generating an extremely large/unplayable output file.

---

Steps to Reproduce

1. Upload a video with no audio track
   OR mute the original audio so hasOriginalAudio evaluates to false
2. Add a background music track
3. Enable “Loop Music”
4. Export the video

---

Expected Behavior

The export should stop when the video duration ends and produce a valid output file.

---

Actual Behavior

The export runs indefinitely because the looped audio stream never terminates.

---

Root Cause

In src/lib/ffmpeg.ts inside buildArguments:

• When loopMusic is enabled, the background music input is prefixed with:

-stream_loop -1

[github-actions]

👋 Thanks for opening an issue, @shahabhilash!

Our maintainers will review this shortly 🚀

Before you start working

• 📖 Read the CONTRIBUTING.md guide
• 💬 Wait for a maintainer to assign you the issue before starting work
• 🔍 Search for existing issues to avoid duplicates

For GSSoC'26 contributors

If you're contributing under GirlScript Summer of Code 2026, please mention it in your comment when requesting assignment:

"I'd like to work on this — contributing under GSSoC'26"

Architecture notes

Reframe is a static Next.js app with output: "export". Key points:

• All video processing uses FFmpeg.wasm (client-side, no server)
• headers() in next.config.ts won't work — use vercel.json instead
• not-found.tsx requires public/404.html + vercel.json routes config

Happy contributing! ⭐ Star the repo if you find it useful!

[shahabhilash]

/assign

[github-actions]

Hey @shahabhilash, this issue has been assigned to you! 🎉 Please make progress within 5 days or it will be automatically unassigned due to inactivity.

[github-actions]

Hey @shahabhilash, just a friendly reminder that this issue has had no activity for 2 days. Please leave an update or let us know if you need help! ⏰

[shahabhilash]

@magic-peach A fix has been implemented and PR #1289 is open for review.

[github-actions]

Hey @shahabhilash, final warning! ⚠️ This issue has had no activity for 4 days and will be automatically unassigned in 24 hours if there is no update.

[github-actions]

This issue has been unassigned from @shahabhilash due to 5 days of inactivity and is open for anyone to pick up — comment /assign to claim it!

[magic-peach]

Thanks for this report! This looks like the same underlying bug as #1577 (infinite export loop / OOM when looping background music on a video with no original audio) — #1577 has a bit more detail on the root cause, so I'm closing this one in favor of that one to keep the discussion in one place. Please jump into #1577 if you have anything to add — reproduction steps, environment details, anything helps!