I cannot hear the audio

ANSWER:
1. Check the connectors between you decoder and the TV set (or Stereo)
2. Press the Mute button on STB RCU and TV to make sure the sound is not switched off
3. Press Vol+ on TV/HomeTheater and STB to make sure the volume level is properly set
4. Try to unplug the power cable of the decoder
5. Try to restore default settings: Menu> Installation> Factory Settings> Yes [default PIN: 1234]