The NO error on your Hisense Smart TV means the television is receiving a picture signal but no audio is being output through the speakers, soundbar, or connected audio device. This is usually caused by a settings mismatch, a loose cable, or a muted output rather than a hardware failure, so it can often be fixed without a technician.

Error code NO
Meaning No sound output detected despite a working picture signal
Severity Low — usually a settings or connection issue, not a hardware fault
Time to fix 5–20 minutes
Tools needed None (occasionally an HDMI or optical cable for testing)

What the NO error means

When your Hisense Smart TV shows the NO sound error, the internal audio processor isn’t sending sound to whichever output is currently active, whether that’s the built-in speakers, an HDMI ARC soundbar, or a Bluetooth headset. The video signal keeps working normally because picture and sound are handled by separate circuits, so a fault only affects one of them. In most cases this points to an audio output setting being sent to the wrong device, a muted volume, or a cable that isn’t seated properly.

Common causes

  • TV volume is muted or set to zero, including a muted external soundbar remote overriding the TV
  • Audio output is set to an external device (like HDMI ARC or Bluetooth) that isn’t connected or powered on
  • Loose or damaged HDMI, optical, or aux cable between the TV and sound system
  • Outdated firmware causing a temporary glitch in the audio processing software
  • Incorrect app-specific sound settings, such as a streaming app defaulting to an unsupported audio format
  • A stuck or corrupted audio driver that needs a power cycle to reset

How to fix the NO error

  1. Check the basics first — Confirm the TV isn’t muted and the volume is turned up, using both the TV remote and any soundbar remote in use.
  2. Verify the audio output setting — Go to Settings > Sound > Audio Output and make sure it matches the device you’re actually using (TV Speakers, HDMI ARC, Bluetooth, or Optical).
  3. Inspect and reseat cables — Unplug and firmly reconnect HDMI, optical, or aux cables at both ends, and try a different HDMI port if using ARC/eARC.
  4. Power cycle the TV — Unplug the TV from the wall for 60 seconds, then plug it back in and turn it on to reset the audio driver.
  5. Update the TV’s firmware — Go to Settings > Support > Software Update and install any available updates, as this often resolves sound-related bugs similar to those covered in Hisense Tv ERROR Error Code: Causes and Fixes.
  6. Reset sound settings to default — If sound still doesn’t work, restore factory sound settings from the menu, then reconfigure your preferred output, similar to the process described in Hisense Tv ERROR Error Code: Causes and Fixes.

FAQ

Why does my Hisense TV have picture but no sound?
This usually happens because the audio output is routed to a disconnected external device, the volume is muted, or a cable connection has come loose, all of which are covered in the fix steps above.

Will a factory reset fix the NO sound error?
Often yes, but try the simpler steps first, such as checking mute settings and cables, since a full reset should be a last resort as outlined in Hisense Tv ERROR Error Code: Causes and Fixes.

Does this error mean my TV speakers are broken?
Not usually. Hardware failure is uncommon; most cases are caused by software settings or cabling, similar to issues discussed in Hisense Tv ERROR Error Code: Causes and Fixes. If sound still fails after all fixes, a warranty check may be needed.