GOG defaults settings to play the CD soundtrack by pointing to start.exe with preset settings when downloaded. If you go into the Epic Inferno Bundle folder where it is installed, open dosbox_epic_single.conf in notepad and find this text or similar:

:inferno
@ECHO off
cls
CONFIG -set "cpu cycles=16000"
cd inferno
imgmount d "..\inferno\game.ins" -t iso -fs iso
cls
start.exe DID=D: quick_flag=1 newflow
exit

Change start.exe or whatever is listed there to conf.exe and you will have access to the game's original config menu where you can change the format of music if you want to try soundblaster or other formats, play around with some test settings, and a few other things. The CD soundtrack is not bad, but I personally grew up with the Soundblaster soundtrack and figured I would share my knowledge of this way of being able to change the music to that format for those in a similar situation. In my opinion this should have been the default through GOG, but whoever set it up to default to start.exe may not have known this is a thing, so I figured I would share.