Some ambients don't show up in Garry's Mod.

Alright, so here’s the deal:
Basically I’m making this metro map, and SOME of my ambient generics (which are identical except for the sound to the ones that work) don’t show up in Garry’s Mod.
They are not custom sounds, they are loops from Episode 1 (which I do have mounted on Gmod)
They DO however show up when I load the map in EP2.
Is this a common problem? Can it be fixed?
Thanks!

Do you have Episode 2 mounted on gmod?

Yes.

Episode 2 content tends to fuck up in gmod quite often. At least from my experiences.

I’ll look into it tomorrow, for now I’ve gotta check that everyone I know is alright after the bombings and shootings.

I saw somewhere that Garry was taking a lot of sounds out because they were hardly used. Thats probably why you can’t hear them.