I think this post is missing details such as what that aftermarket device is and exact model/OS of the mac.
Ok, I bought an hdmi cable a while ago so i could use my tv as a monitor for my mac. I get a great picture but there is no sound from the tv speakers, only the sound that comes from my laptop. Am i able to get sound? Im torn between fixing my mac and buying a new laptop. Id rather keep what i have if i can, but using the tv as a monitor is kind of a big deal for me as I do not have any cablevision etc for entertainment...lol