No sound from soundbar when using an optical cable

If you connected your soundbar to your TCL TV using an optical (TOSLINK/SPDIF) cable but you don’t hear any sound, follow these steps in order.

1) Check the basics first

• Turn the TV volume up and make sure Mute is off.
• Confirm the soundbar is powered on.

Important: With optical, your TV remote may not control the soundbar volume unless the soundbar supports it separately. Use the soundbar remote to raise volume during testing.

2) Make sure the soundbar input is set to Optical

• Most soundbars have multiple inputs (HDMI, Bluetooth, AUX, Optical).
• Use the soundbar Input/Source button and select OPT / Optical / SPDIF / D.IN (label varies by brand).

Tip: If the soundbar is set to Bluetooth or HDMI, you won’t hear audio from the optical cable.

3) Reseat the optical cable (common fix)

• Optical connections must “click” into place.
• Unplug the optical cable from both the TV and the soundbar.

Check both ends:

• Remove any protective caps on the cable tips (if present).
• Plug it back in firmly on both ends until it feels fully seated.

Tip: Optical plugs only fit one way. If it doesn’t slide in easily, rotate the connector and try again.

4) Confirm you’re using the correct ports

• On the TV, the port is usually labeled: Optical, Digital Audio Out, or SPDIF Out
• On the soundbar, the port is usually labeled: Optical In, SPDIF In, or Digital In
• Make sure it’s OUT on the TV → IN on the soundbar.

5) Set the TV audio output correctly

• This is the #1 setting-related cause of “no sound” over optical.
• Go to your TV’s Sound/Audio settings and look for Digital Audio Out / SPDIF / Optical format.

Recommended settings to try (in this order):

• PCM (most compatible — best for testing)
• Dolby Digital
• Auto (if available)
• If your TV is set to Passthrough, Dolby Digital Plus, or another format your soundbar doesn’t support, you may get no audio.

Quick note: Optical does not support Dolby Atmos and may not support certain high-bandwidth formats. If the content is outputting a format your soundbar can’t decode, you can lose sound until you switch to PCM or Dolby Digital.

6) Power reset both devices

• Turn off the TV and soundbar.
• Unplug both from power for 30 seconds.
• Plug them back in.
• Turn the TV on first, then the soundbar.
• Re-select Optical input on the soundbar.

7) Test with different content and isolate the source

• Try a different app (YouTube is a good test).
• Try a different HDMI input/source device if you’re using one.
• Switch the TV temporarily to TV Speakers to confirm the TV is producing sound at all.
• If TV speakers work but optical does not, the issue is likely output format, cable/port seating, or soundbar input.

8) Try another optical cable (if available)

• Optical cables can fail internally, even if they look fine. If you have a spare, swap it in as a quick test.

If you still don’t have sound

• Your soundbar may not support the audio format being sent. Set Digital Audio Out = PCM and retest.
• If PCM still doesn’t work, the TV’s optical port or the soundbar’s optical input may be faulty.