Note- although this is an old thread.
Music is an optional resource.
Meaning, if you want players to get into your server, without being required to have the Hak, then you can simply have them download the music as bmu files, and then download the 2da file as an override resource.
If they put the 2da file in the override directory, it is non-blocking, in that they can get into the server, with or without the music resources.
A hak on the other hand, will kick the players out, if they dont have the hak in their hak directory.