Black Screen but the Sound Plays? HEVC vs AVC

This is the most common problem people write to us about, and it is almost never a broken file. Audio plays, the picture stays black — that combination means the device decoded the audio track fine and could not decode the video track. Usually the file is HEVC and the device is older.

The two codecs you will see

AVC (also written H.264 or x264)

The older standard. Larger files for the same picture quality, but effectively every phone, laptop, browser and TV made in the last fifteen years can play it.

HEVC (also written H.265 or x265)

The newer standard. Roughly half the file size at a comparable quality, which is why it is worth having — but it needs hardware support, and older or budget devices often lack it. When that support is missing you get sound with a black picture.

How to tell before you download

The codec is normally written into the file name, alongside the resolution. A name containing HEVC or x265 is the newer codec; one containing x264 or AVC, or no codec at all, is the older one. If your device has shown a black screen before, choose the second kind.

If you already have a file that will not show a picture

• Try a player that decodes in software. VLC and MX Player can decode HEVC using the processor when the hardware cannot. It uses more battery and may stutter on a slow device, but it plays.
• In MX Player, switch the decoder. Its HW / HW+ / SW decoder setting is exactly this control — SW is the one that works when hardware decoding fails.
• Move it to a newer device. A phone or TV box from the last few years will usually decode HEVC without help.
• Or just take the AVC copy instead. It is a larger download and looks the same.

Sound but no picture in a browser

Browsers are stricter about HEVC than dedicated players are, and support differs between browsers even on the same device. If a file plays in VLC but not in a browser tab, that is the browser, not the file.

The reverse problem: picture but no sound

That is an audio-codec issue rather than a video one, and it often means a track the player cannot decode, or a multi-track file opened on the wrong track. VLC handles almost all of them, and on a dual-audio file you may simply need to switch track — which is the same menu covered in the Subtitles Guide.

The size and label conventions behind all of this are explained further in the Quality Guide.