I leave the manual, check that the audio ic is powered if you see everything well make a reflow to the micro if you do not have clear consult a reflow specialist who fix notebooks know
https://www.electronica-pt.com/esquema/tv/lg-esquemas-tv/lg-47le5500-chassisld03e-led-lcd-tv-17657/
look at this, when not a lg with reballing problems
https://rosario.olx.com.ar/rebaling-placa-main-lg-42ld650-42ld655-47le5500-42le5500-iid-945544013