# HDMI settings


> The low-level HDMI controls on Raspberry Pi based screens: what each one is for, and why you should not touch them unless a display is misbehaving.
> [!IMPORTANT]
> Leave these alone unless you have a display problem you cannot solve any other way. Every one of them defaults to letting the player and the display negotiate, which is right nearly always. The commonest way to break a working screen is to set one of these to a value the display cannot do.

These appear on Raspberry Pi based screens when video output is HDMI.

## HDMI group and mode

**HDMI group** decides which set of resolutions the player picks from.

**EDID** is the default and means "ask the display what it supports". **CEA** is the television set of modes, **DMT** the computer monitor set. Choosing either of the latter then enables **HDMI mode**, a numbered list within it: mode 16 is 1080p at 60 Hz in CEA, mode 82 is 1080p at 60 Hz in DMT.

Set these only when a display reports its capabilities wrongly, which shows up as a picture at the wrong resolution or no picture at all.

## HDMI drive

**Auto**, **HDMI mode**, or **DVI mode**.

DVI mode sends no audio, by design. If a screen has a picture but no sound and everything else looks right, this is the setting to check.

## HDMI boost

A signal strength from **0** to **7**. Raising it can rescue a picture that breaks up or drops out over a long or poor-quality cable.

Try a shorter or better cable first. Boost compensates for a bad run; it does not fix one.

## Pixel encoding

**Auto**, or one of four explicit combinations of RGB and YCbCr at limited or full range.

The symptom that points here is a picture where blacks look grey and whites look dull, or the opposite, where dark detail is crushed to solid black. That is a range mismatch between player and display. Forcing **RGB full (0-255)** or **RGB limited (16-235)** to match what the display expects fixes it.

## Force hotplug

Makes the player output video whether or not it detects a display.

Turn it on when a screen shows nothing because the display was powered on after the player, or because a signal extender or matrix switch between them hides the display from the player.

## HDMI timings

A raw timing string for a display that fits none of the standard modes. If you need this you already know the values, and if you do not have them from the display's manufacturer, this is not the setting to experiment with.