I amazedly realized that the musics files of JA was missing.
And........there's problem with CD-room . I wonder if I could get it....
Just open up the pk3 files with pakscape or winzip and extract the mp3's. Then you can listen to them whenever you want or create an audio cd from them using some third party program.
If you mean the mp3's are somehow "missing" from the assets pk3's, then you can get them back by reinstalling the game from the original discs, no problem.
As for problems with the CD, check the Technical Support forum. A scratched or dirty cd-rom can be easily cleaned with any cleaning kit and it should work again.
Please note, if you're using a cd cracked or otherwise less than legal version of the game we can't provide any help for you, and likewise nobody will send you the assets files or their cd key. So don't ask for that!
if you have no music, you probably got a rip version of the game illegally, go buy it, its really cheap now.