How to output sound from TV to home theater via HDMI

Connecting a modern speaker system to the screen is the foundation for creating a high-quality home theater. Simply turning on the power is not enough, as the audio stream must be routed correctly to avoid delays and loss of quality. Most modern users prefer to use a digital interface HDMI, as it provides the bandwidth required for Dolby Atmos and DTS:X formats.

The setup process may seem complicated due to the abundance of ports and menu options, but in reality it comes down to a few logical steps. The key to success is understanding the difference between a regular HDMI cable and versions that support a return channel. If you want to get the most out of your system, you'll need to understand ARC and eARC technologies and set up the audio output on your TV correctly.

Choosing the right cable and checking compatibility

The first step is to physically connect the devices. Not all cables are created equal, and using an outdated cable may result in no sound or only two channels. For full operation of modern soundbar or receiver requires a standard cable High Speed or Ultra High Speed.

Pay attention to the markings on the wire insulation. If you plan to use ARC or eARC features, make sure the cable is certified to carry data in both directions. Standard HDMI 1.4 cables support basic ARC, but require version 2.1 to transmit uncompressed audio.

• 🔌 HDMI 2.0 cable - suitable for 4K and basic ARC, but may not support eARC.
• 🔌 HDMI 2.1 cable - ideal for Dolby Atmos and high-speed data transmission.
• 🔌 Ethernet cable - built-in conductor inside HDMI for transmitting an Internet signal (rarely needed for sound).

The length of the cable also plays a role. When using passive conductors longer than 5-7 meters, the signal may degrade. In such cases, it is recommended to use active optical cables or extension cords.

⚠️ Warning: Using cheap cables without proper shielding may result in noise, crackling or complete blankness of the screen when the load on the channel is high.

Physical connection and port location

After selecting the appropriate wire, you need to find the correct connectors on the device body. Most TVs have multiple HDMI ports, but not all of them support audio return. Usually the required port is marked with a special inscription or icon.

Look for markings HDMI ARC or HDMI eARC on the back of the TV. The cable coming from the input is connected to the same connector. HDMI OUT (TV ARC) on a home theater. It would be a mistake to connect to a regular HDMI IN, since the signal will only go in one direction.

If you are using a receiver, the diagram may be different. The signal from the source (for example, a game console) first goes to the receiver, and then through HDMI OUT to the TV. This allows the receiver to process the sound before it is output to the speakers.

Make sure the cable is firmly seated in the connector. A weak connection often causes intermittent sound dropouts, which is very annoying when watching movies. Reliable connection — the key to stable operation of the entire system.

Activating ARC and eARC in TV settings

Physical connection is only half the battle. The default TV may not send audio to the external device, thinking it should play through its built-in speakers. You need to go to the system menu and change the output parameters.

Go to section Settings → Sound → Sound Output. Depending on the manufacturer, the menu name may differ. Samsung has it Sound settings, LG has Sound, at Sony - Settings. Find an item Speaker control or Speaker system.

Select an option Audio system or Audio output. After this, activate the function ARC or eARC. If there is no such option, check whether CEC (Consumer Electronics Control) mode is enabled, as it is often responsible for automatic device discovery.

• 📺 For Samsung: Settings → General → External devices → Anynet+ (HDMI-CEC).
• 📺 For LG: Settings → Advanced → Sound → SPDIF/Audio Out → HDMI ARC.
• 📺 For Sony: Settings → Display and sound settings → Sound → Sound output → Audio system.

It's important to note that the eARC feature requires more advanced settings. If you see an "eARC Mode" switch, make sure it is turned on if your receiver supports this standard. This will allow you to transmit high-resolution, uncompressed audio.

⚠️ Attention: If you do not activate the CEC/Anynet+/Simplink function, the TV may not recognize that an audio system is connected to it and the sound will continue to come from the built-in speakers.

Home theater and receiver configuration

Now it’s the turn of the sound receiver. Turn on your home theater and check if it can see the signal source. The device display should show the name of the connected TV or the “HDMI ARC” status.

In the receiver menu, go to the section Connection settings or Sources. Make sure that the port to which your TV is connected is selected as the active input. Some models require manual switching to HDMI 1 or HDMI 2, even if the cable is connected to a port labeled TV.

Check your decoding settings. If the TV transmits a signal in PCM format, the receiver will simply pass it through. To obtain surround sound, the TV must stream in the format Dolby Digital or DTS, and the receiver was decoding it.

What to do if the TV is not visible to the receiver?

1. Reboot both devices by completely disconnecting them for 30 seconds. 2. Check if the power supply is overheating. 3. Try another HDMI port on the TV, even if it is not marked as ARC, sometimes this helps to find the conflict. 4. Update your TV's firmware to the latest version, as older versions of the software may have bugs with eARC support.

Comparison of audio interfaces

While we're focusing on HDMI, it's helpful to understand how it differs from other interfaces. This will help you evaluate the benefits of your current configuration and understand why the optical cable may be inferior.

The HDMI ARC/eARC interface allows audio to be transmitted in both directions. This means that you can control the theater volume from your TV remote. An optical cable (Toslink) transmits sound only in one direction and does not support modern compression formats.

Below is a table comparing the main characteristics of interfaces for audio transmission.

Interface	Max. bitrate	Format support	Volume control
HDMI ARC	37 Mbit/s	Dolby Digital, DTS	Yes (via CEC)
HDMI eARC	37 Mbps (compressed), 128 Mbps (uncompressed)	Dolby Atmos, DTS:X, TrueHD	Yes (priority function)
Optical (Toslink)	5.4 Mbit/s	Dolby Digital, DTS (no Atmos)	No (requires separate remote control)

As can be seen from the table, HDMI eARC is the only solution for owners of systems that support new generation surround sound. Optical cable is obsolete for the task of transmitting multi-channel uncompressed audio.

Troubleshoot common problems

Sometimes, despite correct installation, the sound does not appear. The most common cause is a protocol version conflict or outdated software. Try performing a hard reboot.

Unplug the TV and cinema for 2-3 minutes. This will reset the HDMI cache and temporary settings. After turning on, check the audio output settings again.

If there is sound, but it is interrupted or you hear clicking, the problem may be in the cable. Try replacing it with another one, preferably certified High Speed. Also check if the power line is overloaded, as interference may affect digital signal transmission.

• 🔧 Reset sound settings: return all settings to factory settings and configure again.
• 🔧 Software update: go to the manufacturer’s website and download the latest firmware.
• 🔧 Checking the source: try playing the video from another device (flash drive) to eliminate bugs in the streaming application.

In rare cases, changing the HDMI settings in the advanced developer menu helps, but this requires caution. Do not change the settings if you are not sure of their purpose, so as not to disrupt the operation of the interface.

⚠️ Attention: If after all the manipulations there is no sound, check whether the sound is blocked on the TV itself or in the application that you use to watch content.

Optimizing sound quality

Once the sound is working, you should pay attention to its quality. Modern TVs often have built-in equalizers, which may conflict with movie theater settings. It is recommended to disable all sound enhancers on the TV itself.

Turn on the mode Straight pass (Pass-through) or Bitstream in the TV settings. This will allow you to transfer the original audio stream to the receiver without pre-processing, which guarantees maximum quality and correct operation of surround sound decoders.

Set up video and audio synchronization (Lip-sync). If the sound lags behind the picture, use the appropriate function in the receiver or TV menu. This is usually done by adjusting the delay in milliseconds.

For best results, use playback modes that match the genre. In movies, select the mode Cinema, in music - Music. This will activate the necessary signal processing algorithms in your soundbar or receiver.

Frequently asked questions from users

Can I use an HDMI cable to connect to an old TV?

If your TV doesn't have an HDMI port, you won't be able to use this method directly. You will need an analog output (RCA or SCART) to HDMI converter, but this will require additional power and may degrade sound quality.

Why does the sound work, but there is no surround effect?

Most likely, the video source transmits a signal in Stereo (PCM) format. Check the settings of the application or player in which you are watching content and switch the audio track to 5.1 or 7.1 channels.

Do I need a special cable for ARC?

Technically, any high-quality HDMI cable version 1.4 and higher is suitable. However, for stable eARC performance, it is strongly recommended that you use certified HDMI 2.1 cables marked "High Speed" or "Ultra High Speed".

Is it possible to connect two devices via one HDMI port?

No, one HDMI port only supports one device. To connect multiple sources you will need an HDMI splitter (splitter), but to transmit sound to a theater it is better to use a switch (switch).

What to do if the TV doesn't control the theater volume?

Check if CEC (Anynet+, Simplink, Bravia Sync) is enabled on both devices. If this doesn't help, try disabling and re-enabling the ARC feature in your TV's settings.

Properly setting up HDMI audio output unlocks the full potential of your home theater. Don't neglect updating firmware and using quality cables. By following these recommendations, you can enjoy cinematic sound without unnecessary problems and technical difficulties.

Only using an HDMI 2.1 cable and enabling eARC mode guarantees the transmission of uncompressed Dolby TrueHD and DTS-HD Master Audio without loss of quality.