First of all, I want to warn you that perhaps they read a lousy English, this is what came out of the Google XD translator, I do not speak English, but I hope they can understand me and give me their help.
I have a LG 42LB6500-UM TV that apparently has a problem with the Firmware, since I bought it I had automatic updates configured, so it was updated several times until arriving at the mysterious Firmware 05.00.15. Why mysterious? Because according to the support page of LG this software is not in the compatible history with the model of my TV. Here the problem began.