It's a feature, not a bug,
JJM is disableing the JJ-internal music / sound system because of stability of its own system, since JJ2 often block the soundcard for other sound services... (this is written in JJM's Readme too), JJ's internal music system can be enabled when you change in the JJMConfig.ini
"Disable JJ Music at Startup=1" to 0.

(when you ignore the sounds of JJ2 (like jumping, running,...) and the fact that the format .j2b is not included in JJM yet JJM replace JJ's music system complete and add internet Streaming to it)

Since I had problems with my Server some parts of JJM-Music (Streaming Part) are not working, but this is for this at the moment not relevant (will be fixed at next update).

I dont know how often I said it, JJM is at the moment not a finished working program, I'm really happy that its working for the most users stable since the last version and that some users are highly interested in it, but at the moment JJM is ONLY for interested players that want to TEST a little addon that operates similar like plus (even if it is a external program) and thats the reason, why I never made a JCF Thread (reason was asked by some players) for the program...

Finally:
If a user know how to configurate JJM, read the Readme and inform himself at carrotus.com the user can enable / disable ALL features JJM give.

Sfaizst