PCM Audio on Hisense TV: Configure the Output

Should you set your Hisense TV to PCM?

PCM is one of the format choices for a Hisense TV's digital audio output, which is the optical port or HDMI ARC/eARC. With PCM selected, the TV decodes the soundtrack itself and sends uncompressed audio to the soundbar, receiver or converter. Choose PCM if the connected output device cannot decode Dolby or DTS, or if other modes give silence, dropouts or crackling. If your system decodes surround formats, choose Auto or pass-through instead, because PCM over optical or standard ARC is limited to two channels.

Menu names and layout differ between Hisense platforms, models and firmware versions. Look for the sound option that controls the format of the digital output. This is separate from the option that chooses between the TV speakers and an external device.

• Connect the sound system with an optical cable or to the HDMI port labelled ARC or eARC on the TV.
• In the TV's sound settings, set the audio output to the external device rather than the built-in speakers.
• Find the digital audio output format option and select PCM.
• On the soundbar or receiver, select the matching input (optical, ARC or TV).
• Play content you know has sound and confirm audio plays steadily, with no gaps or noise.

How PCM output works

PCM (pulse-code modulation) is digital audio stored as a plain series of samples, without the compression used by Dolby Digital or DTS. A digital output can carry audio in one of two ways. In PCM mode, the TV decodes the soundtrack and sends the result as PCM. In bitstream or pass-through mode, the TV forwards the compressed stream unchanged, and the sound system does the decoding.

The connection type sets the limits. Optical can carry compressed surround formats, but its PCM is two-channel only. Standard ARC behaves much the same way in practice. eARC was designed to carry multichannel PCM, but whether a given Hisense model actually sends it depends on the model and firmware. Check the specifications for your TV and sound system rather than assuming.

A PCM stream also has a sample rate, which the receiving device has to accept. Many receivers and soundbars show the incoming format on their display. If yours shows PCM after you change the setting, the TV is sending what you selected.

Choosing the right mode for your setup

• Stereo soundbar or older amplifier on optical with no Dolby decoder: PCM is usually the correct choice.
• Optical-to-analog converter feeding powered speakers or a headphone amplifier: many of these converters accept only PCM, so select it.
• Surround receiver or soundbar that decodes Dolby or DTS: use Auto or pass-through. PCM over optical or ARC folds the mix down to stereo.
• eARC soundbar with Dolby Atmos: keep Auto or pass-through, and use PCM only as a troubleshooting step.
• No sound, intermittent audio or crackling in bitstream mode: switch to PCM to check whether the problem is format compatibility.

Streaming boxes, game consoles and Blu-ray players connected to the TV have their own audio format settings. If one source has trouble while built-in apps play correctly, set that device's output to PCM or stereo as well. That rules out a format the TV cannot pass on.

Limits and related questions

Is PCM better quality? For stereo content, PCM delivers the decoded audio without further compression. For surround soundtracks sent over optical or standard ARC, choosing PCM means losing the extra channels. Which mode is better depends on what your sound system can decode.

Lip-sync offset is a separate issue. Changing the format can alter processing delay, so if speech drifts out of sync, use the audio delay or lip-sync adjustment on the TV or sound system if one is available. Some models handle volume differently for the digital output, so check whether the TV remote or the soundbar remote controls the level.

The PCM option only affects the digital audio leaving the TV. Hiss or hum from analog speakers, a weak input level on the amplifier, or background noise picked up by a TV camera or voice remote microphone come from other parts of the chain. If your model supports a camera or microphone for calls, that is an input device with its own settings, and changing the output format will not affect it. Bluetooth headphones also use a separate audio path, so the digital output format generally does not apply to them.

Firmware updates can rename or move audio options. If the PCM option disappears or behaves differently after an update, check your model's current manual or support notes rather than relying on older instructions.