My Slinbox is connected to a Tivo box at home. I have had Slingbox on Mac for a year without issue. I turned it on today and I get no sound, however, if I go into my taped shows in Tivo, the sound plays. All mute buttons on the Mac as well as home (remote controls, TVs etc) are all off. The Mac has sound otherwise. The only time I lose sound is when I try to watch live TV. The volume at home is okay and at proper level.