The soundtrack is being sold seperately through Amazon mp3 -
http://www.amazon.com/Gray-Matter-Original-Soundtrack-Game/dp/B0047WQZ3I

But you can listen to it on YouTube - http://www.youtube.com/results?search_query=gray+matter+soundtrack
And Spotify - http://open.spotify.com/album/3Pb3HjOPKhNLvwMPAXkguV (credit to Kattus for that link)

EDIT: Amongst the installed files, the music is within "xwb files (e.g. MusicBank.xwb), probably from Microsoft XNA Game Studio. There are some community tools to extract them, but VirusTotal.com doesn't give a green light on any of t hem so I refrain from testing it. Within the xwb files are supposed to be single xWMA files that can be converted to WAV via xWMAEncode.exe, which is part of the DirectX SDK." - DeMignon

If its not listed as a bonus, very unlikely.

It's happened in cases like Pandemonium, Interstate '76, and Hotline Miami. GOG might not be able to include the OST separately but it is obviously still part of the game, which can mean it is in a folder like "gog.com/gray matter/sound/music". Or it may need to be extracted from the game files.

We don't have the soundtrack available but I can appeal to my managers at Viva Media to see if such assets are available. I was happy to see that we could get our game on GOG as an entry into the world of DRM Free for Viva Media.

Very nice! Thumbs up and +1

Thanks. Do you know if the music is amongst the installed files, perhaps as mp3 files? (I don't have the game.)

The description does not say we include a sound track so I think it's a safe bet to say that we don't have it in this version of the game. But it can't be ruled out that possibly in the future we could offer this as added additional content. I can email the people who made it happen and see if they can find something.

Oh, so there's no music when you play the game? That seems a little odd, but not a huge deal.

There is music in the game but the music is its own proprietary file thats not another format unless you had some tool to disassemble the file.

Are you comfortable sharing what file format that is? Personally I think people who legally own the game should be able to extract the music if they can.

I'm not allowed to give this information out.

I understand. Perhaps somebody else will be able to provide that info eventually. EDIT: Or by "proprietary" perhaps you meant a special/custom file format specifically made by the devs to seal the music up.

They're xwb files (e.g. MusicBank.xwb), probably from Microsoft XNA Game Studio. There are some community tools to extract them, but VirusTotal.com doesn't give a green light on any of t hem so I refrain from testing it. Within the xwb files are supposed to be single xWMA files that can be converted to WAV via xWMAEncode.exe, which is part of the DirectX SDK.

Ah okay, thanks!

Yes, I would definitely love the soundtrack to be made available here. Always.

Thanks for your responsiveness and efforts!