Ready I found the fault ... it was located at the power source ... the KIA78R12 regulator at its output had only 7volt replace the filters but it was still the same voltage..I had to replace the regulator..you realize the fault because you have all its voltages the source but on pin 15 of the IRS2092 ic 19volts of error appear and place the audio in mute ... enter protection for a poor voltage ... I invite you if you are an LG brand technician that you also add your failures in this page of yoreparo and we can continue to help these are failures that do not describe the user manual .. greetings