# A video stutters or doesn't play

Szenera converts videos that players can't play, such as iPhone recordings, by itself. If a video still stays black or stutters, the cause is usually the player's power supply, a file that is too large for the device, or the browser of a TV.

> **Type:** troubleshooting
> **For:** anyone whose video doesn't play smoothly on a display
> **Prerequisite:** none
> **Where in the portal:** **Media** and **Displays** › display › **Overview**

## The video stays black or is skipped

Check its status in the library. A video plays only once it shows **Ready**. Videos in a format the players can't decode, such as HEVC from an iPhone or 10-bit video, get a playable version first, and that can take a few minutes. The library accepts only MP4 and WebM files.

## The video stutters on a player

- If the portal shows **Power supply throttling**, the player gets too little power. Use the power supply that came with it and a short cable.
- The Player Lite plays video up to Full HD, the Player Pro up to 4K. Szenera makes a Full HD version of larger videos, but until it is ready, the original plays. Upload Full HD videos for the Player Lite.
- If the portal shows **Storage low**, the player may not be able to load the next video. Remove content you no longer use.

## The video stutters on a TV app or in a browser

TV browsers decode less than a player. On older TVs, a transition between two videos becomes a hard cut, because the TV can only decode one video at a time. That is intended and not a fault. Use the format below and short transitions, or a player in front of the TV.

## The video has no sound

Videos from your library always play without sound. For sound, use the [YouTube](/apps/youtube) or [Live stream](/apps/stream) app.

## The video ends too early or freezes at the end

In a playlist, a duration you enter for a video wins. A longer video is cut off, and a shorter one holds its last frame. Leave the duration field empty, and the video runs its natural length. See [Create a playlist](/programs/create-playlist).

## Videos on a video wall don't line up

All displays of a video wall switch at the same moment, but videos across the seam aren't frame-accurate. For video walls, use scenes, images, and calm transitions, see [Set up a video wall](/displays/create-video-wall).

## The format that works everywhere

| What | Recommendation |
|---|---|
| File | MP4 |
| Video codec | H.264 |
| Resolution | 1920 × 1080, and 3840 × 2160 only for the Player Pro |
| Frame rate | 25 or 30 frames per second |

> **Tip:** A free tool such as HandBrake converts any video to this format. A Full HD video for a display rarely needs more than 10 Mbit/s. Larger files only take longer to load and cost storage.

## Related

- [File types, sizes, and storage](/content/file-types-and-storage)
- [Create a playlist](/programs/create-playlist)
- [Which hardware do you need?](/devices/choose-hardware)