Sonos Arc with LG OLED no sound: what is usually happening?
If your Sonos Arc with LG OLED no sound issue appeared after a new setup, software update, or source change, the problem is usually in the HDMI eARC path, TV audio output settings, or a format mismatch.
The good news is that most cases can be fixed without replacing hardware.
The Sonos Arc relies on the LG OLED to send audio over HDMI ARC or eARC, so even a small configuration error can mute the entire system.
Understanding where the signal is breaking makes troubleshooting much faster.
Check the physical connection first
Before adjusting menus, confirm the basics.
A loose cable or the wrong HDMI port is one of the most common reasons an LG OLED and Sonos Arc stop producing sound.
- Connect the Sonos Arc only to the TV’s HDMI ARC or eARC port.
- Use the high-speed HDMI cable that came with the Sonos Arc if possible.
- Remove and firmly reseat both ends of the cable.
- Check for bent pins, damaged connectors, or a loose fit at the soundbar.
- Bypass HDMI switches, splitters, and AV receivers during testing.
On most LG OLED models, the ARC/eARC port is labeled on the back panel.
If you connect the Arc to a standard HDMI input, audio return will not work.
Verify LG OLED audio output settings
LG OLED TVs need the correct audio output selection to send sound to Sonos Arc.
If the TV is set to internal speakers or a different external output, the Arc may appear connected but remain silent.
Settings to review on the LG TV
- Set Sound Out to HDMI ARC, HDMI eARC, or HDMI (depending on the model and menu wording).
- Turn eARC support on if your TV and Sonos Arc both support it.
- Set Digital Sound Output to Pass Through when available.
- Disable TV speakers if the TV keeps switching back to them.
For many LG OLED models, the best combination is HDMI eARC with Digital Sound Output set to Pass Through.
This allows Dolby Digital, Dolby Digital Plus, Dolby Atmos, and other compatible formats to reach the Sonos Arc correctly.
Make sure CEC is enabled on both devices
Sonos Arc depends on HDMI-CEC for volume control and TV communication.
On LG televisions, this feature is often called Simplink.
If CEC is off, the Arc can lose control signals and sometimes fail to negotiate audio properly.
- On the LG OLED, enable Simplink (HDMI-CEC).
- On Sonos, ensure TV autoselect and remote control setup is complete in the Sonos app.
- Power cycle both devices after changing CEC settings.
CEC issues often show up as more than missing sound.
You may also notice that the TV remote no longer adjusts volume or the Sonos app reports a poor TV connection.
Confirm the audio format is compatible
A mismatched audio format can cause a Sonos Arc with LG OLED no sound problem even when everything appears connected.
This is especially common when watching a device set to output an unsupported format or a streaming app configured incorrectly.
Sonos Arc works best with standard TV audio formats such as stereo PCM, Dolby Digital, Dolby Digital Plus, and Dolby Atmos through compatible eARC or ARC paths.
Some LG OLED models or attached sources may attempt to send formats that are not handled correctly in a given setup.
Try these format checks
- Switch the TV audio output to Pass Through.
- Test with a built-in LG app such as Netflix, Disney+, or Apple TV.
- Temporarily set the source device to output Dolby Digital instead of Bitstream or Auto.
- Disable forced surround formats on game consoles or streaming boxes while testing.
If sound returns when using a built-in app but not an external device, the issue is likely with that source’s audio settings rather than the Sonos Arc itself.
Power cycle the TV, Sonos Arc, and sources
A clean restart often clears handshake failures between the LG OLED and Sonos Arc.
HDMI ARC/eARC communication can get stuck after firmware updates, power outages, or switching cables.
- Turn off the LG OLED, Sonos Arc, and any connected source devices.
- Unplug all of them from power for at least 60 seconds.
- Reconnect the Sonos Arc to the TV’s ARC/eARC port.
- Power on the TV first, then the Arc, then the sources.
This sequence gives the TV a chance to recognize the soundbar and rebuild the audio link.
If the TV still fails to detect the Arc, repeat the process once after confirming the cable is secure.
Update firmware on LG OLED and Sonos
Software updates can fix HDMI compatibility bugs, but they can also temporarily introduce problems until both devices are on current versions.
If your Sonos Arc with LG OLED no sound issue started after an update, check both systems.
- On the LG OLED, open the settings menu and check for a TV firmware update.
- In the Sonos app, confirm the Arc is updated to the latest software.
- Restart both devices after any update completes.
Firmware mismatches are a common source of eARC handshake issues, especially after a TV update that changes HDMI behavior or audio routing defaults.
Test with a different HDMI cable
Even high-quality cables can fail or become unreliable over time.
If the Arc worked before and suddenly stopped, a damaged or marginal HDMI cable should be part of the diagnosis.
Use a certified high-speed HDMI cable, ideally one known to support ARC or eARC reliably.
Keep the cable short enough to avoid unnecessary signal loss, and avoid very cheap adapters or long extensions.
When testing, change only one variable at a time.
If a new cable restores sound, the previous cable was the source of the problem.
Check the Sonos app for TV audio status
The Sonos app provides useful clues when the TV connection is unstable.
It can show whether the Arc is receiving audio, whether the system sees the TV, or whether there is an error in setup.
Useful app checks
- Open the Sonos app and verify the Arc appears online.
- Review the room’s TV audio status if available.
- Run TV setup again if the app suggests the connection is incomplete.
- Check whether any recent change to home theater tuning or voice settings coincided with the sound issue.
If the app shows the Arc as connected but there is still no sound, the issue is more likely in the TV’s output path or the HDMI handshake than in the speaker itself.
Inspect source devices and app-specific behavior
Sometimes the LG OLED and Sonos Arc are working properly, but one source is sending broken audio.
This is common with streaming boxes, gaming consoles, cable boxes, and Blu-ray players.
Try multiple sources:
- LG built-in apps
- Apple TV
- Roku
- PlayStation or Xbox
- Cable or satellite box
If only one device produces no sound, adjust that device’s audio settings.
If all sources fail, focus on the TV’s HDMI settings, the cable, or the Sonos Arc setup.
Reset only after basic troubleshooting fails
A factory reset should not be your first move.
Because it erases settings and may require reconfiguration, use it only after checking the cable, TV audio output, CEC, and format settings.
Before resetting, note your current LG OLED and Sonos configuration so you can restore important options afterward.
In many cases, a power cycle and a settings correction solve the issue without a reset.
When to suspect a hardware fault
If you have confirmed the correct HDMI port, tested multiple cables, verified TV output settings, and updated both devices, a hardware issue becomes more likely.
Possible faults include a damaged HDMI port on the TV, a failing Sonos Arc input, or an internal board problem.
Signs that point toward hardware trouble include:
- No sound from any source despite correct settings
- Repeated disconnects after every reboot
- The TV never recognizes the Sonos Arc
- Visible HDMI port damage or looseness
At that stage, contact Sonos Support or LG Support with your exact TV model, firmware version, and a summary of the steps you already tried.
That information helps narrow the issue quickly.
Fast troubleshooting sequence for Sonos Arc with LG OLED no sound
If you want the shortest path to a fix, use this order:
- Confirm the Arc is plugged into the LG OLED ARC/eARC port.
- Set LG Sound Out to HDMI ARC or HDMI eARC.
- Enable Simplink and eARC.
- Set Digital Sound Output to Pass Through.
- Restart the TV, Arc, and source devices.
- Test with a built-in LG app.
- Try a different HDMI cable.
- Check source audio settings if only one device is silent.
This approach resolves most Sonos Arc and LG OLED audio issues by isolating whether the problem is physical, software-related, or source-specific.