I was just working through this problem on my Sony Bravia 4K TV. My PS4 suddenly has no sound one day. TV menu HAS sound. The final fix was a SECRET FREAKING RESET OPTION IN THE TV. I did not find ANY guide that mentions this. It’s in the “About” section of the TV. Not in Settings, not in Audio or Inputs or Help section. In the stupid freakin ABOUT section. There’s your make, model, and a button to restart the tv that fixes it perfectly. I was so frustrated after hours of searching for what caused my sound to stop working.