The TV supports only PCM (Pulse-code modulation) or two-channel audio. So, the TV displays this error if it receives an unsupported audio signal from the output device. To fix this error, change the audio output settings of the connected device to PCM.
IMPORTANT: Make sure your Android TV™ has the latest software installed. Downloads are posted on your model support page.
Note: Contact the device manufacturer for assistance or refer to your device's manual for further details.