> ## Documentation Index
> Fetch the complete documentation index at: https://docs.dfine.app/llms.txt
> Use this file to discover all available pages before exploring further.

# Playback and processing

> Fixes for files that are still processing, will not preview, or only offer a download.

After an upload we prepare an optimised copy for the browser. Most playback problems come from that step or from a codec the browser cannot decode.

<AccordionGroup>
  <Accordion title="My file is still processing" icon="loader">
    After upload we prepare an optimised version. You see **"Preparing your video for processing."** and then a progress display. Give it a moment, then refresh.
  </Accordion>

  <Accordion title="The video could not be optimized, but is available for download as original." icon="triangle-alert">
    The optimised copy failed, but your original is safe. Download the original to view it, or upload a re-encoded MP4 (H.264). Contact support if it keeps failing.
  </Accordion>

  <Accordion title="Playback stops and the page reloads itself" icon="rotate-ccw">
    In a live session you see **"Media playback failed. Reloading page."**, in the review player **"Playback refresh failed. Reload the page."** Both mean a network or codec hiccup interrupted playback. Let the page reload, check your connection, and try the latest Chrome or Safari.
  </Accordion>

  <Accordion title="The audio will not play" icon="volume-x">
    Some audio codecs do not play in every browser. If you see a decode error, download the file, or re-encode the audio as MP3, AAC, WAV or FLAC, which play everywhere.
  </Accordion>

  <Accordion title="The file only offers a download" icon="download">
    Some formats, such as PSD, camera RAW and office files, are stored for download rather than browser preview. Download the file to view it locally. See [Compatibility](/en/review/compatibility).
  </Accordion>
</AccordionGroup>

<Card title="Still stuck?" icon="life-buoy" href="mailto:support@dfine.io">
  Write to [support@dfine.io](mailto:support@dfine.io) and we will help you out.
</Card>