This problem just suddenly started the other day. i don't think I even did an update or anything to windows and have no clue what caused it. I have always been able to get picture and sound on the tv when I hook the laptop to it with the HDMI cord. But seemingly overnight now the sound only plays on the laptop and only the picture on the tv. Anyway I'm pretty sure this is a windows 8 issue. I upgraded to windows 8.1 to see if it would fix the problem and it didn't.
I'm thinking its a driver issue.....usually is.
Please help!