That's true, it was Solar Fields, if you will check my workshop, you can find a "sneaky soundtrack mod" without a pic there, it features solar fields as ambiet and other artists, emphasizing space atmoshere a lot, I really like it :P
>x3 music mod may have added a track from subnautica
I think you confused it with something else, I didn't even played subnautica at the moment when I was making that mod

ah great taste in music dude. Yeah i believe i did have the sneaky soundtrack mod... guess i didnt realize it had music from solar fields because i got stuck on the x3 music mod. :)