I figured out that the Long Range Music Bricks have this capability.
Pecon was the one who unintentionally discovered it, and I pinpointed what it was.
How to do it:
Download the Long Range Music Bricks addon from RTB.
Make some stereo loops and add their entries in your musicList.cs.
Use a dedicated server. Launching a regular non-dedicated server will cause BL to delete the files.