When the TV is set to [EasyLink autostart] mode in the Home menu > [Setup] > [TV settings] > [Sound] > [Advanced] > [TV speakers] menu, the TV prompts the HDMI-CEC connected device to switch to system audio mode. The TV will turn off the TV’s speakers automatically and starts to stream audio through the connected HDMI-CEC audio device.
If you are not connected to a HDMI-CEC audio device, disable the [EasyLink autostart] mode.