Black screen, endless spinning, no sound or videos that won't start? Playback problems on Threads usually come from the connection, data-saving settings, an outdated app or browser, or a problem with one video. Run the quick check below, then follow the fixes for what you see.
They solve most "video won't play" problems. Tick them off as you go.
Start with number 1.
Test the device you're using now. It checks your connection and settings and plays a tiny built-in test clip. Nothing is sent anywhere.
On a phone, run this in your normal browser. It tests the browser, which shares most settings (data saver, connection) with the Threads app.
Exact menus by phone: iPhone settings finder · Android settings helper · Threads on desktop fixes
If every other video works, the problem is probably the post, not your device.
The creator may have removed it or changed who can see it. Refresh the feed.
Just-posted videos can take a few minutes before they play everywhere. Try again shortly.
Some videos are limited by region, age or a content warning. Tap through the warning if there is one.
Your own video black or silent? Re-export and post again - see export settings.