Help (Cod4) Thread

I use lot of custom maps. In many cases player become bored while downloadingm aps from slow speed ftp server and quit game
I have seen in other servers that the have added music in mod and when a client begans to download custom maps the music automatically played
I can also do that but don't know whats name of the music file be
Know there is a specific name don't know what. Any idea?
Thanx