So, I was looking through the sound files of the addon (via Extended Spawnmenu) and noticed a batch of files labeled "Transmission1-10" (I don't know where they actually play in the map), and decided to listen to them.
And then I realized they're pieces of heavily distorted music (or at least the ones I recognized).
So, in order, these are the bits of music I recognized.

Transmission 1 - Minecraft Soundtrack - The End
Transmission 4 - Wii Shop Channel Main Theme
Transmission 5 - Xbox 360 Startup Theme
Transmission 6 - It's Raining Somewhere Else/The Place Where It Rained (hard to tell which one it is)
Transmission 7 - C418 - Dry Hands

Transmissions 2, 3, and 8-10 were unrecognizable/unknown to me, so... if anyone else can tell what they are, please say so.

That, or Grey themselves could just say what they are.