Sound but no picture: fix a black video screen on Windows

When a video plays its sound over a black screen, the sound track was decoded and the picture track was not. On Windows the usual reason is that the video inside the file is HEVC (H.265) or AV1, and the PC has no decoder for it. AIX Player carries its own decoders, so the picture and the sound arrive together, with no codec pack to install.

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Windows 11 & 10 · Guide reviewed 28 October 2026

Why you hear it but cannot see it

A video file is a box holding separate tracks: one for the picture, one or more for sound, perhaps some subtitles. A player decodes each track on its own. If it can read the AAC or Dolby Digital sound but has no decoder for the HEVC or AV1 picture, it plays the sound and leaves the screen black, or shows an error. Renaming the file from .mkv to .mp4 does not help: it changes the label on the box, not what is inside. The video formats page explains containers and codecs in more detail.

Fix it step by step

1. Open the file in AIX Player. Install AIX Player from the Microsoft Store, then in File Explorer right-click the video, choose Open with and pick AIX Player. HEVC, AV1, H.264, VP9 and the other common video codecs are decoded inside the app, so nothing else needs installing.
2. Still black? Turn off hardware decode. Open Settings → Video → Hardware decode and switch it off. It is on by default and uses your graphics chip to decode video; switched off, the processor decodes instead, which rules the graphics path out.
3. Update your graphics driver. Install the current driver for your NVIDIA, AMD, Intel or Snapdragon graphics. AIX Player’s Help page says where to get each one.
4. Check the file itself. Make sure the download or copy finished. A file that stops at the same point every time, or plays nowhere, is usually incomplete or damaged.

If the video is HDR

On an ordinary (SDR) screen, AIX Player tone-maps HDR video to fit the display, so you see a normal picture rather than a dark or washed-out one. HDR playback is part of AIX Pro, and the free app includes a separate HDR allowance: see what is free and what Pro adds. Ordinary video, including 4K and 10-bit, is free without a time limit.

See which codec a file uses

Open the file’s details in AIX Player. It lists the video type, the audio, the resolution and the bitrate on one screen, which tells you whether the picture is HEVC, AV1 or something older. If the file is an MKV, the MKV troubleshooting guide covers the other problems those files can have.

Picture missing only on the TV?

If the video plays on the PC but not on the television, the TV is the part that cannot decode it. Start with the casting guide for your device; AIX Player converts the part a TV cannot play while it streams.