Answer to: chrome os is missing or damagedThis can be easy to fix if you haven't already. You will lose all of your local data, though. If it ever says that, press Refresh+Power and it will reset it. If you still see this, press CTRL+D to "enter" developer mode. When it has a RED exclamation point (not a YELLOW) press space to re-enable OS verification. It will wipe local data, reset your operating system and you should be good to go.
Answer to: Volume has a piercing soundHas there been a thunderstorm lately or anything that would surge your power? Also, is your TV plugged into a surge protector or not?
Answer to: Not powering on. Never opened.Normally I WOULD say that it is the actual display (the screen BEHIND the glass), since Samsungs are notorious for doing that. However, you have had it working for 3 days so... I've got nothing. Sorry for my uselessness X-P