Ripping audio from a Sega CD .iso

[Dew]

I'm trying to get a track off of an .iso for Dungeon Master II: Skullkeep on the Sega CD. Namely the theme for the last boss, which I remember hearing as a kid when I loaded the actual physical CD in player mode on the system. That CD and the system, however, are both in a box somewhere in my parents' basement two states away. I figured I could just take this .iso and play it the same way I would an audio CD, but none of my media players recognize it, and the audio isn't visible when exploring the disc. I've read that a mac recognizes it as two discs, one audio and one data, but I can't confirm this. Also, I tried running both GENS and Fusion in CD player mode, but for some reason that doesn't produce any sound. I see the dB meters moving for the left and right channels, but I don't hear anything. The game itself plays fine and has music.

Is there anyone here with better knowledge of how this works?

Sorry for asking about ROMs and whatnot, but I own the game in question, I simply don't have access to it at the moment.