Personally I think it might also be easier to convert the audio to your own close captions in more real time and higher quality ( and better than what the broadcast typically gives you) and leave the sound on low. I like the crowd noise and the announcers, but I also like my sanity more.
Donate to a non-profit that hires dystopian fiction authors to patent the technology in their stories, wait 500ms for some jackass to try to implement the dystopia, sue them for damages and enjoin them from continuing to do it. Donate half the proceeds to the EFF and use the other half to file more dystopian patents.