The Samsung CU8000 has one HDMI port marked ARC, usually HDMI 3, for sound to a soundbar or receiver, and when the soundbar is silent or cuts out, the cause is nearly always the port, the cable or the audio setting. Connect the soundbar's HDMI output marked ARC or eARC to the TV's ARC port with a good HDMI cable. A soundbar in any other port is treated as a source feeding the TV, which is the wrong direction for sound. In the TV's settings, open Sound, Sound Output and choose the HDMI or Receiver option rather than the TV speaker, and in Expert Settings set HDMI Input Audio Format and Digital Output Audio Format to a mode your soundbar accepts, Pass-Through or PCM.
The checks in more detail
Turn on Anynet+, Samsung's name for HDMI-CEC, in Settings, General, External Device Manager, because the ARC handshake relies on it. PCM is the safest format, as every soundbar decodes it. A soundbar that cannot handle a surround format the TV passes through will be silent. The CU8000 supports standard ARC, which carries compressed surround such as Dolby Digital, not the lossless formats of eARC, so the soundbar will not show the highest quality formats.
On the soundbar itself, pick the ARC or TV input and raise the volume. If the TV remote cannot change the soundbar's volume, Anynet+ is probably off. If there are dropouts or clicks, replace the cable, since a poor HDMI cable breaks the ARC link. Cut the power to both: switch them off, pull both plugs for a minute, then return power and switch the soundbar on before the TV.
Install the latest TV software from Settings, Support, Software Update, and look for a firmware update for the soundbar. For lip sync, use the audio delay setting in Sound, Expert Settings. If you also have a game console on the soundbar, connect it to the TV instead so the chain does not confuse the handshake. Compare with the optical output if both have it, to see whether the soundbar is at fault. Samsung support, given the model number, is the next step if ARC still fails with a good cable, the right port and Anynet+ switched on.
In a home theatre, the order of switching on matters. Some soundbars wake up more slowly than the TV and miss the first seconds of sound, which is a handshake delay, not a fault.
Turn the soundbar on first and then the TV, or give them a minute. Check that no other device, such as a game console, is set as the active audio device by Anynet+, which can take the sound path away from the soundbar. If you use a universal remote, make sure it does not send a mute or an input change when the TV starts. The CU8000 is one of Samsung's Crystal UHD sets, and it has a single port marked ARC, which is the only HDMI input that can carry sound back to a soundbar.
It does not have eARC, so a soundbar that expects Dolby Atmos from eARC will play standard Dolby Digital or stereo instead, which is a limit of the TV and not a fault. Check which port is marked, and use a standard high-speed cable.
Differential
Likely causes of “Samsung CU8000 Crystal UHD TV ARC or eARC soundbar audio is not working”, and how to tell them apart
- 1
The soundbar is not on the ARC port
What separates it No sound from the soundbar
How to confirm Use the port marked ARC
- 2
Anynet+ off
What separates it The handshake fails
How to confirm Turn it on
- 3
The wrong output or format
What separates it Silence or crackle
How to confirm Select the HDMI output and change the digital format to PCM
- 4
A poor HDMI cable
What separates it Dropouts
How to confirm Replace the cable
- 5
Standard ARC limits
What separates it Lossless formats do not play
How to confirm Expect compressed surround
Before you touch a setting
Record this first — changing settings destroys the evidence
- The port used
- The sound output and format
- The soundbar model
- Whether Anynet+ is on
Try in this order
0 of 6 completedUse the ARC port
ReversibleWith a good cable.
Turn on Anynet+
ReversibleIn External Device Manager.
Set Sound Output
ReversibleTo the HDMI receiver.
Set the audio format
ReversibleTo PCM or Pass-Through.
Power cycle both devices
ReversibleSoundbar first.
Update both
ReversibleTV and soundbar.
Model-specific
What is true of this model and not of its siblings
- ARC port
- One HDMI port.
- Anynet+
- Needed for the handshake.
Stop boundary
When this stops being a self-service repair
- !Phone Samsung with the model number if ARC fails despite a good cable and Anynet+
- !Test the optical output
- !Update both devices
Evidence ledger
Sources behind this answer
Exact questions
Common questions
Which port is ARC on the CU8000?+
The one marked ARC.
What is Anynet+?+
Samsung's HDMI-CEC.
Does it support eARC?+
Standard ARC, not eARC.
Which format is safest?+
PCM.