MacBook connected to TV via HDMI, but sound only plays from MacBook

I am using an HDMI to connect my macbook to my tv. Once connected, the sound will still only come out of my macbook. I have already tried changing the sound output in my settings; however, it only caused buffering issues on the tv display and did nothing to the sound.

[Re-Titled by Moderator]

Original Title: Macbook Sound Issues w/ HDMI