I used CC for the same reason as many. Speech audio is of poor quality, back in the old days in my CRT television it wasn't a problem. Speech was clear. Now for whatever reason it's too loud for comfort if I want to hear the words. My tv has speech clarity options but it is marginal at best.

I'm using a Roku streambar with a couple of wireless speakers. Still poo audio. And I'm not convinced a system of higher cost and quality would solve it.