An LG B3 OLED whose soundbar or AV receiver will not play TV sound over eARC or ARC has a connection, a port or a setting problem, and the B3 has one detail that catches people: the HDMI ports are not all the same. This 2023 entry OLED runs webOS 23, and only two of its four HDMI ports are full HDMI 2.1 with 4K 120 hertz; one HDMI port is also the eARC port, which carries audio back from the TV to a soundbar. If the soundbar is plugged into a port that is not the eARC port, no sound will come, however the settings are set. Find the right port.
The checks in more detail
Look at the labels on the TV's HDMI ports: one is marked eARC or ARC, and the soundbar's HDMI cable must go from that port to the soundbar's HDMI eARC or ARC port. Use a high-speed or ultra high-speed HDMI cable; a poor or a very long cable can drop the audio, and a cable that is not fully seated causes dropouts. On the soundbar, select the input that matches the connection, usually labeled TV, ARC or eARC. On a receiver, set the HDMI input for the TV. Then the TV settings. Go to the Sound menu, choose Sound Out and select the HDMI ARC option that names eARC, so audio leaves through the port and not the TV's own speakers.
Turn on HDMI CEC, called SIMPLINK on LG, in General, so that the TV and the soundbar can control each other, and make sure that the soundbar also has HDMI-CEC enabled. If you hear no sound, switch the TV and the soundbar off, unplug them for a minute and plug the soundbar back in first, then the TV; this renegotiates the link. Look at Digital Sound Output; Auto or Pass-through suits most soundbars, and PCM is the safe choice when a format will not decode. Update the TV software and the soundbar.
If a console is plugged into the eARC port for gaming and the soundbar into a non-eARC port, swap the two, using a 2.1 port for the console. When nothing changes the result, try a second HDMI cable, then phone LG with the model number.
Because the B3 has only two HDMI 2.1 ports, plan the back of the TV before you plug things in. A console that needs 4K 120 hertz and a soundbar that needs eARC both want special ports, and the eARC port is separate from the two 2.1 ports. If your soundbar is a Dolby Atmos model, choose a cable rated for eARC, as an old cable may carry stereo but not Atmos. Also check that the soundbar's own settings allow the TV to control its volume, so that the Magic Remote changes the soundbar's level; if it does not, SIMPLINK or the soundbar's HDMI control is switched off. After a power cut, the TV and soundbar can lose their link, and a power cycle restores it.
Differential
Likely causes of “LG B3 OLED TV ARC or eARC soundbar audio is not working”, and how to tell them apart
- 1
The soundbar not on the eARC port
What separates it No sound from the soundbar
How to confirm Use the labeled eARC or ARC port
- 2
A poor or loose HDMI cable
What separates it Dropouts or no audio
How to confirm Use a high-speed cable and reseat it
- 3
The wrong sound output or no SIMPLINK
What separates it The TV plays on its own speakers
How to confirm Choose HDMI ARC and enable SIMPLINK
- 4
An audio format the soundbar cannot decode
What separates it Silence or crackle
How to confirm Set Digital Sound Output to Auto or PCM
- 5
A stale link
What separates it The soundbar is not detected
How to confirm Power down and unplug, then reconnect
Before you touch a setting
Record this first — changing settings destroys the evidence
- Which HDMI port the soundbar uses
- What Sound Out is set to
- Whether CEC is on
- The soundbar model
Try in this order
0 of 6 completedUse the eARC port
ReversibleLabeled on the TV.
Use a good HDMI cable
ReversibleSeated firmly.
Set Sound Out
ReversibleTo HDMI ARC.
Enable SIMPLINK
ReversibleOn the TV and soundbar.
Power cycle both
ReversibleSoundbar first.
Contact LG
ReversibleIf it still fails.
Model-specific
What is true of this model and not of its siblings
- Port roles
- One port is eARC and two are HDMI 2.1.
- Sound Out
- It must be set to HDMI ARC.
- CEC
- SIMPLINK lets the devices talk.
- Cables
- A poor cable drops audio.
- Power order
- Soundbar first, then TV.
- LG help
- Quote the model number.
- Planning the ports
- Only two ports are HDMI 2.1, and a third is the eARC port.
- Atmos
- Atmos over eARC needs an eARC-capable cable and soundbar.
Stop boundary
When this stops being a self-service repair
- !Do not force an HDMI plug
- !Switch off before moving the TV
- !Contact LG if no port carries audio
Evidence ledger
Sources behind this answer
Exact questions
Common questions
Why will my soundbar not work with my LG B3?+
The wrong port, a cable or the sound setting.
Which port is eARC?+
The one labeled eARC or ARC.
Does it use a 2.1 port?+
The eARC port is separate from the 2.1 ports.
What is SIMPLINK?+
LG's name for HDMI CEC.
Which format should I choose?+
Auto or Pass-through; PCM if needed.
Do I need a special cable for Atmos over eARC?+
Use a certified high-speed or ultra high-speed cable that supports eARC.
Why does the Magic Remote not change the soundbar volume?+
SIMPLINK or the soundbar's HDMI control is off.