Do you have more than one Origin account? Is it possible you're trying to use the wrong one by mistake? Double-check that the Origin account you're playing DA on is the same one you're using to try and get the soundtrack. If you're on PC, you can check your account pretty easily: just log into Origin and go to your profile, you should see your user name and the e-mail address it's connected to. Can't remember how you can do this on the consoles, but if it's in any way similar to how DA:O and DA2 work, you should be able to check the Origin ID your game is connected to from the start menu somewhere.
You could always try to log out in-game and log in again to see if that solves the issue. Also you should probably check that you have enabled data sharing - I hadn't, which was why none of my characters were uploaded to the Keep.
Don't have the game yet myself so I'm not 100% sure this will solve your problem, but these are the most usual causes for the online-account related "can't access DLC / my profile isn't updated" -problems.
I have one that was APPARENTLY made some time in 2011, and is connected to my LIVE account, but even when I figured out how to get on that one and logged on, went to dragonage.com and logged in in-game and all that jazz, it still said 'This is for Deluxe/Inquisitor editions only. If you have either of the above, play the game before you come here.'
I play on the 360 so figuring out which account, if either of the two I've access to, is the proper one, seems to be a bit difficult. Nowhere on the start menu, or the Options menu, or the Multiplayer menu, have I been able to find an Origin ID, but I may just not be looking in the right nooks and crannies. I tend to do that.