>> Listen for any movement in the room, then if the coast is clear try to open up the vent and go in.

C: “…static? Wonder where it’s coming from. Might be something I can use…”

You listen carefully, even closing your eyes for a moment to concentrate on listening. Movement…. You don’t hear any in the room. It’s completely silent. No, not quite silent, there’s a low, almost inaudible hiss of static coming from somewhere.

The vent comes open easily, it seems the screws are missing here too…

Well, that means that at least one thing is going right.