Looks like you have to make a mod to put in music!

:S

As far as I know, custom music (unless we're talking SP/local only) isnt possible.

Go here:
C:\Program Files\Electronic Arts\Battlefield 2142\mods\bf2142

Then look for the zip named Sound_client

Unpack it

Add in the .ogg file (needs conversion, but thats found in other tuts) into the sounds/music area of these unpacked files (there should be other music from other levels there) name it e.g. My_Music

Repack it into the Sound_Client

Then go to:

C:\Program Files\Electronic Arts\Battlefield 2142\mods\bf2142\Levels\Level_name\info

And open DESC.doc

Change the music section

<music> sound/music/My_Music.ogg </music>

Save it, and all should be peachy

Hope this helps those that fall as hard as I do!

¬.¬

Sorry to have bothered you

C:\Program Files\Electronic Arts\Battlefield 2142\mods\bf2142\Levels\Level_name\sound\music\War

My DESC.doc file says this

<music> sound/music/War.ogg </music>

I can't really do much else...or think of anything to do

Then edit your .desc file in your info folder. 

<map>
    <name> Your_Map_Here </name>
    <briefing locid="LOADINGSCREEN_MAPDESCRIPTION_Your_Map_Here">map description for modders maps not localized (english only)</briefing>
    <music> Music/Your_music.ogg </music>
    <modes>

At least that's what I remember.   I believe if your linking to a song in the common.zip files you link to sounds/music/Your_music.ogg

It's been a year or so since I messed with that, but that is what I remember.

I saw you guys already got it in, may I ask how?

Edit: I already have it in .ogg format, I just don't know where to put it and how to link it with code