I have 55B6V and I'm having the same sound issues via optical out. Recently bought new active speakers and switched to optical and now the audio cuts out a couple of seconds every hour. Very annoying. I tried all settings and switching cables, nothing worked. I have the same problem no matter what source (PS4, Xbox, streaming or TiVO) I use. Getting desperate now, because I tried contacting LG customer service and they just told me to try different settings on the TV. Well, none of them worked and I notice I'm not the only one with this problem. Does anyone have a suggestion?
EDIT: Note that I don't have a soundbar but I have the exact same problem described in this thread /EDIT