This is a combination of it being slightly bright but the main issue is that it is displaying in greyscale.
This isn't really the case, or at least from July 13th(latest stream where someone rode ToT, however the preshow still had lighting on dim), the speakers were all over the place. The ones closest to the show shafts are more quiet, and are more louder towards the drop shaft. Not only that, but the BGM/SFX and narration/extra SFX/BGM track for the 5D were slightly out of sync from each other. This was more noticeable on Foxtrot side, though I am unsure if this is just because the BGM track became much more louder at the starfield doors, because before, you would mainly only hear the narration track at the starfield doors while the main BGM track would sound distant.
Speaking of the starfield doors, they are still wonky(or at least since July 13th).
It depends when "before" is, but on Foxtrot side, (again at least from July 13th) the drop shaft speakers are MIA. Even then on Echo side, the drop shaft speakers are still somewhat quiet. The main way to tell is if you hear the lightning strike SFX entering into the drop shaft, that only plays from the drop shaft speakers.
This video shows what the drop sequence audio levels should sound like:
One thing I miss from this period is the ominous drone from the thunder SFX when entering the drop shaft.