Need a small hint

[Echoes, Spiraling]

I've given the train conductor automaton the documents and ticket, I've placed the mammoth doll in the train and I put one of the audio cylinder things (the one hidden in the bookshelf in the factory office) on the train shelf. I still need the third object (I'm guessing it's a second audio cylinder) to make the train go.
I'm trying to finish this game without looking up a walkthrough, so does anyone have a small hint they could give me? I feel like the solution is something I'm really close to, like everything else that's happened in the game so far.

[mikeydsc]

Did Oscar give you any plans to make the train go that you have to work out? Plus a 2nd cylinder is needed as suspected. There is a puzzle to solve to get the train moving.

[Echoes, Spiraling]

So far all Oscar has said is that I need three items in place. I don't think he's given any clues as to where the other cylinder is.

[WarriorD2]

You need to go to the church area.
Dont forget to save your game because there is a annoying bug over there. Sometimes the main door of the church crash the game. You better dont use that door because its useless you wont need to open that door.