I am trying to connect a Vizio smart tv to a samsung sound bar with hdmi. i've plugged the hdmi into the ARC input on my tv and the hdmi in the tv out on the soundbar but still have no sound. i've also turned off the tv speakers. i've tried every source on the soundbar and i'm still not getting anything. My hdmi cord is a little order. Do you think it isn't ARC compatable? is this new technology? or am i doing something else wrong?
What is the TV model? You may have to be on a specific HDMI, ie, HDMI 1 or HDMI 2, in order for it to work. You will need to know which port, if any, carries the ARC signal and is compatible. It may be that none do if the manufacturer has chosen not to implement it. A new cable might be necessary, as indicated in this article that addresses the same questions you have posed:
If you have ARC in the TV and soundbar you should only have one HDMI connection. ARC is audio return channel. Your TV doesn't have an HDMI output so a second connection is not possible. You will need to turn ARC on in the TV menu for it to work.