Video Troubleshooting

Upload problems

• Upload fails: convert to MP4 (H.264), try a wired connection, and try another browser. Very long files take a long time; upload them when you can leave the tab open.
• Allowance reached: your library holds 10, 50 or 100 hours of video by plan. Remove videos you no longer use or upgrade.
• Stuck at the end: processing has started. It can take several minutes for long files. Do not close the tab until the upload itself has finished.

Playback problems

• Will not play: wait for processing to finish, then try another browser or a private window.
• Blurry at first: higher qualities finish processing last. Give it a few minutes.
• No sound: check the source file has audio, and the browser tab and device are not muted.
• Out of sync: re-export the source with a constant frame rate.
• Buffering: the player adapts quality to the viewer's connection; buffering usually means a slow connection at their end.

Embed problems

• YouTube: the video must be Public or Unlisted, with embedding allowed. Use the full youtube.com address.
• Vimeo: check the privacy settings allow embedding on other sites.
• Removed video: the original was deleted or made private. Replace the embed.

Phones and tablets

Ask the student to tap play once; mobile browsers wait for a tap before playing.

Recording settings that avoid trouble

MP4 container, H.264 video, AAC audio, 1080p, 30 frames per second, constant frame rate.

When to write to us

Uploads that fail with several different files, processing that has not finished after two hours, or a video that plays for you and for no student. Tell us the course, the lesson, the file format and size, and your browser.