On the TCL QM8 (2024), a soundbar belongs on the one HDMI input labeled ARC or eARC, which one 2024 review lists as HDMI 4; the two HDMI 2.1 inputs are for consoles and PCs and carry no soundbar audio. Plug the soundbar's HDMI OUT (eARC/ARC) into that port with a high-speed cable, switch on HDMI CEC, and choose the HDMI ARC output in the TV's audio settings. If a movie goes silent while TV apps still play, the soundbar probably cannot decode the format being sent: set the digital audio format to PCM first and try Dolby Digital and Atmos afterwards. After any change, switch the soundbar on, give it ten seconds, then start the TV so the link negotiates in the right order.
Differential
Likely causes of “TCL TV line ARC or eARC soundbar audio is not working”, and how to tell them apart
- 1
The soundbar is in the wrong HDMI input
What separates it The TV is silent and the soundbar shows no signal
How to confirm Move the cable to the TV input labeled ARC or eARC and keep the soundbar's HDMI OUT (ARC) on its own output
- 2
HDMI CEC is off
What separates it The TV remote cannot change the soundbar's volume or power
How to confirm Turn on HDMI CEC in the TV settings and on the soundbar, then test the remote
- 3
The soundbar cannot decode the format
What separates it Movies and streaming apps go silent while system sounds still work
How to confirm Set the digital audio format to PCM, then try Dolby Digital before Atmos
- 4
A slow or stale link
What separates it Sound is missing right after power-up, or after a setting change
How to confirm Turn off both devices, power the soundbar first, wait ten seconds, then start the TV
- 5
A weak cable
What separates it Sound cuts out or crackles
How to confirm Swap in a short high-speed cable that you know works
Before you touch a setting
Record this first — changing settings destroys the evidence
- Which TV input the soundbar plugs into and what its label says
- Whether CEC is on for the TV and the soundbar
- The digital audio format currently set on the TV
Try in this order
0 of 6 completedFind the labeled port
ReversibleLook at the labels on the back of the QM8 and use the input marked ARC or eARC for the soundbar, not an HDMI 2.1 gaming input.
Turn on CEC
ReversibleEnable HDMI CEC in the TV settings so the TV remote follows the soundbar.
Choose the ARC output
ReversibleIn the TV's audio settings select HDMI ARC as the audio output.
Set PCM first
ReversibleSet the digital audio format to PCM, check sound, and only then try Dolby Digital or Atmos.
Restart in order
ReversibleSwitch both off, power the soundbar, wait ten seconds and start the TV.
Try another cable
ReversibleTest a different high-speed HDMI cable if sound still drops out.
Model-specific
What is true of this model and not of its siblings
- HDMI layout
- One 2024 review lists four HDMI inputs: ports 1 and 2 are HDMI 2.1 and ports 3 and 4 are HDMI 2.0, with port 4 as the eARC input; check the labels on your unit.
- Other models this page answers
- These steps also fit the Q7 QLED Google TV, 6-Series Roku TV R655, 6-Series Google TV R646, 4-Series Roku TV S455.
Stop boundary
When this stops being a self-service repair
- !If it stays silent on the labeled ARC or eARC port with a good cable and PCM selected, contact TCL
- !A soundbar that is silent on every device needs checking itself before the TV is blamed
Evidence ledger
Sources behind this answer
ARC setup.
CEC control.
Soundbar HDMI.
Input, cable and reset steps.
The company and its products.
HDMI port layout and eARC port.
Exact questions
Common questions
Which HDMI port on the TCL QM8 is the eARC one?+
Use the one printed ARC or eARC. A 2024 review lists HDMI 4, and the two HDMI 2.1 inputs are meant for consoles and PCs.
Why is a TCL QM8 silent on movies but fine on menus?+
The soundbar cannot read the format being sent. Setting the digital audio format to PCM fixes it on most soundbars.
Can I get Dolby Atmos from the QM8 to my soundbar?+
The QM8 supports Dolby Atmos, so an eARC soundbar can receive it over the labeled port; use PCM if Atmos is silent and try again after updating both devices.
Should the TV speakers be off while I test?+
Yes. Some TVs keep playing through their own speakers and hide whether the soundbar is receiving anything.