Mute icon always active

[AndrewGr3]

On my UE40MU6120 TV Smart I have the "mute" icon flashing all the time, and the volume doesn't increase or decrease.

[Ginga_p]

Have you tried reseting all in the sounds section in main menu

[lminvti]

Hi there 👋 and welcome

Try press and hold mute button on your remote for 3-5 seconds. Also, check input settings if you're using any soundbar.
You can also try and reset tv by pressing and holding power button on your remote for 5 seconds