env_microphone trouble

I have a map where a train is a part of the 3d skybox, and I want it to play a noise based on its position in the skybox, and relay it back to the actual map. I know it can be done but I'm using a cheaper route. I wanted to use an env_microphone placed in teh skybox to relay the movement noise of the train to an env_speaker placed in the real map. The only problem is, It doesn't play any noises. I placed a zombie in the skybox and made it angry and it still didn't make any noise. The only noise that works is the one I had triggered to play when the train stops at a station directly below you that you can't reach.

How do I get the microphone to play the exact sounds played in the skybox?

EDIT:

Ok I managed to get the test zombie to make noise and it works fine. But the func_tracktrain I placed in the skybox still doesn't seem to pick up. Is this a bug?

---

What makes life so great is that its there.

Maybe.. The train isnt making a noise at all.. have you checked that?

---

What do i put here again?

The train is making plenty of noise. It seems to be the only thing not being transmitted.

---

What makes life so great is that its there.