Route audio through other HDMI Port of a NUC

[bmike1]

I want to route the audio through the other hdmi port of my dad's NUC. I read somewhere that you need to do that if you want to connect it to a sound system but it just occurred to me that things might already be set up that way. SO the questions are do I need to route it and how do you do it.?
Inquiring minds want to know!
My search through the forum didn't reveal anything.