When the TV’s built-in speakers and an external speaker (such as a soundbar) play audio at the same time, you may hear an echoing sound.
This is typically caused by a slight audio delay (latency) because the TV and the soundbar process digital signals at different speeds.
To resolve this issue, change [Digital Sound Output] to [PCM], or use only one speaker output. If you are using a soundbar, you can also correct the audio delay by adjusting [AV Sync].
Why is the sound echoing or out of sync?
- Digital Signal Processing Delay: When the audio output is set to [Auto], a slight delay may occur while the device processes the digital signal. This can cause the two outputs to overlap, creating an echo effect.
- Simultaneous Output (Echo): When [TV Speaker + External Speaker] is enabled, the sound may echo due to the distance between the speakers or differences in speaker performance.
How Do I Fix Echoing or Out-of-Sync Sound?
How to change [Digital Sound Output] to [PCM]
Setting [Digital Sound Output] to [PCM] sends the audio signal without additional compression, which reduces processing delay and helps prevent echoing.
- 2021 and later [webOS 6.0 and later]: Press [Settings] on the remote → Select [All Settings] → [Sound] → [Advanced Settings] → [Digital Sound Output] → [PCM]
- 2020 and earlier [webOS 5.0 and earlier]: Press [Settings] on the remote → Select [All Settings] → [Sound] → [Advanced Settings] → [Digital Sound Out] → [PCM]
➔ Changing [Digital Sound Output] to [PCM] on 2025 and later TVs (webOS 25 or later)
- 1. Press the [Settings] button on the remote, then select [All Settings] in the top-left corner of the TV screen.
- 2. Select [Sound], then select [Advanced Settings].
- 3. Select [Digital Sound Output] and set it to [PCM].
Use Only One Speaker Output
Instead of using simultaneous output, select either the TV speakers or the external speaker. Using only one output helps prevent echoing.
- 2021 and later [webOS 6.0 and later]: Press [Settings] on the remote → Select [All Settings] → [Sound] → [Sound Out]
- 2020 [webOS 5.0 and earlier]: Press [Settings] on the remote → Select [All Settings] → [Sound] → [Sound Out]
➔ Changing the output speaker on 2025 and later TVs (webOS 25 or later)
- 1. Press the [Settings] button on the remote and select [All Settings] in the top-left corner of the TV screen.
- 2. Select [Sound], then select [Sound Out].
- 3. Select your desired output speaker.
Adjust [AV Sync] on the Soundbar
If you are using a soundbar, adjust AV Sync to better match the audio with the on-screen video (lip sync).
- Press the [AV Sync] button on the soundbar remote.
- Check the soundbar display, then press the Left/Right arrow buttons to adjust the delay.
- If you’re using an LG soundbar, you may be able to adjust the setting more easily using a supported smartphone app. Check your user manual for supported apps.
※ Note: Steps and feature availability may vary by model. Refer to your product’s user manual for details.
Frequently Asked Questions (FAQ)
- Q. The sound is out of sync only when I watch Netflix or YouTube.
- A.If the issue happens only in certain apps, it may be a temporary app issue. Unplug the TV’s power cord, wait for 1 minute, and then plug it back in (reset). Check if a new update is available for the specific app and install it.
- Q. Why do I hear an echo even though I haven't changed any settings?
- A. The TV’s default setting may be set to [Auto]. In [Auto] mode, the TV analyzes and processes audio signals. Compared to an external speaker that outputs sound without that processing, the TV audio may play slightly later.
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This guide was created for all models, so the images or content may be different from your product.
