I recently updated my Sony XBR-65A1E to Android 8, and the TV sound didn't work after the update. Sound from HDMI devices came through, however with no volume control or mute capability. The menu sound effects worked. I tried poweroff-poweron, restart (My restart is located at Settings->About->Restart ),factory-reset(which took forever),restart again,factory-reset again(which went much quicker the second time-odd), and finally restart again while on the main menu screen after volume-up and NOT muted. The last restart fixed the audio, as good as new or better with the android/system upgrade. I have no idea whether all of those actions are necessary, but that's what I did, and my system-updated XBR-65A1E TV audio works again. Be aware that the factory reset fully erases the TV's data, so all personalizations and customizations (settings) are lost. The restart function is like a power cycle/hardware reset (power-off then power-on) and does NOT appear to erase or change any settings. Also, I forgot to mention...