@neodev I'm experiencing the same, that is, not working without disabling seek time emulation myself.
I'm using an original unmodified US Genesis 1, and the US disc image. Using US Sega CD v2.00w bios. Looks like the game serial matches with Dampfwalze's image above for the US version.
Again, this is just a few seconds of music that is played after defeating a boss, the rest of the music works. I'll keep my CFG file in place for now.
Sorry for the lousy image, but I figure it's good enough as it is readable.