Only one conclusion can be drawn from this. It’s them, Chara.
Interestingly, many minor NPCs like the royal guards [x] use this same voice blip. That doesn’t mean Chara’s voice can be dismissed since regardless of this they blatantly state their own name, but it does mean the blip could be a more generic or placeholder sort of voice sound. Alternatively, it could mean that Chara is relaying the things the more minor characters say. Who knows! I’d be interested to hear other theories on it.
The narration still has the same syntax, which is clearly Chara’s, but a much harsher sound. It also uses “I”,
so it’s obviously Chara. What could this mean? Maybe Chara’s putting on their serious voice, and then still making Star Wars jokes. Who knows. That much we’ll have to resign to theory.
But wait, you cry! What about their silence when they appear at the end of No Mercy?
But this isn’t the only time someone does this while being a dramatic asshole. The other person who accompanies their text with a spooky silence is none other than…
(He also does this in the judgement hall on all routes except a No Mercy. Drama queen.)
Therefore, the silence doesn’t seem terribly significant.
So, there you have it. Simple evidence for a simple fact: Chara’s the narrator in all routes, in both red text and white, and the pacifist and neutral routes are just as important to understand their character as No Mercy.