My Vizio has picture, but no sound.

I recently decided to use my roommates TV while he was out of town. I unhooked my Xbox One from my working Vizio TV (Model ) and hooked it up to his bigger LG tv. When I went to hook my Xbox back into my Vizio, the picture is still there, but I can't seem to get sound. I've followed all the tips for fixing the tv, but nothing still. I know this is a TV related issue, since I've hooked my Xbox into several other TV's and it works fine, but I can't even hook up a laptop without getting a muted picture. Please help!