Downloaded video has no sound? Here's why

The real cause: two streams, not one

Big video platforms don't store high-resolution video as one file. To let the player switch quality smoothly, they keep the picture and the sound as separate streams and combine them as you watch. On YouTube that's the case from 720p upward; Facebook does the same for HD.

A downloader has to fetch both streams and merge them into a single file. Tools — and some browser extensions — that grab only the video stream hand you a file with a perfect picture and no soundtrack at all.

First, check which problem you have

Open the file in VLC, which plays almost any format, and see what happens:

• Silent in VLC too — the file has no audio track. VLC's media information (Tools › Codec Information on Windows, Window › Media Information on Mac) lists the streams; you'll see video only. See fix 1.
• Sound in VLC, silent in your usual player — the audio is there, but your player can't decode it. See fix 2.
• Sound everywhere except your editing app — the editor doesn't support that audio format. See fix 2.

Fix 1: download it again with the audio merged

If the file has no audio track, nothing can add it back — the sound was never downloaded. Get the video again from a tool that merges the streams. Every option on the Video tab here is merged with its audio before the file is handed over: paste the link into the YouTube downloader or the Facebook downloader and download it again with the sound merged in.

Fix 2: the audio is there but can't be played

WebM files usually carry Opus audio, which some players, TVs and editors don't support. The picture plays; the sound doesn't. Either play the file in VLC, or download the MP4 version instead, whose AAC audio plays everywhere. MP4 vs WebM explains the difference.

Fix 3: you picked a video-only option

Some tools list raw streams with labels like “video only” or “DASH video”. Choosing one of those gives you a silent file by design. Here, the Video tab only offers complete files with sound, and the Audio tab is sound only — there's no silent option to pick by mistake.

Which platforms cause this

The problem depends on how each platform stores video:

• YouTube — anything above 720p is stored as separate streams, so this is the most common source of silent downloads.
• Facebook — HD versions are stored separately; SD usually includes sound.
• Instagram, Loom and Dailymotion — silent downloads are much less common.

If it's still silent

A few less common causes are worth ruling out:

• The original has no sound — some videos are published silent, or with the audio muted for copyright reasons. Check it on the platform.
• The download didn't finish — an interrupted file can lose its audio. Download it again.
• The sound is very quiet or on one channel — try headphones before assuming it's missing.

For other errors, Fixes & FAQ lists each symptom with its cause and fix.