When you hear people talking ingame, the game is using something called WAC. the WAC for your mission is nonexistant until the MED makes one, the original med that came with the game doesnt have that option, you can download the unlocked med that does a lot more here:
http://www.dfbarracks.com/downloads/...ion=df&fid=150
When you open that med, theres an option for opening the WAC under the tools tab, there is where the med makes the wac file. But now you have a wac file, but its empty. here you can download the tutorial on how to work up a wac.
http://www.dfbarracks.com/downloads/...ion=df&fid=201
and now for music, once again, you'll need the unlocked MED. In the general information screen, at the bottom, in global effects, theres music and a small text bar. 1 through 20 a legit. In order to start the music, you need to make area triggers. and theres a lot to explain and some of the research i have to give credit to others. You can see the thread here on dfbarracks
http://www.dfbarracks.com/forums/vie....php?tid=27889