Confused about the audio output of the PS4

Jun 25, 2013
Doesn't the PS4 output 7.1? I'm confused, because when I got my A50s 2 days ago the only options I saw was for 5.1 and 5.1 DTS. Guess it's not a huge deal since the Astro TX simulates 7.1 audio, but I was under the impression the PS4 was 7.1. Can anyone enlighten me? Thanks.