I've tried to set the Music Volume to 0 in the Sound option, but I still can hear it. Will I have to delete/rename the music files, or is there other way?

There is an other way.

Find the configuration file of dosbox (dosboxCarma.conf probably)
open it with notepad and add below the line that starts with imgmount
MIXER CDAUDIO 0:0

Thanks Qbix; at first it didn't work, but I realised I was using the hardware mode, so I included the line in the dosboxCARMA3dfx.conf, and now it's fine.

They included original Iron Maiden soundtrack? How on earth could they do that?

...Fear Factory.

Carma 2 was Iron Maiden. Carmageddon 1 is Fear Factory.

They probably had the rights to include the music with the game set back in 97 or whatever. What interests me is how they did it technically... getting the game to play saved files instead of tracks off a CD must have been hard.

Just FYI: if you don't want to completely disable the music but just lower the volume, put a value like 40:40 instead of 0:0
They're actually percentages for the left:right channels.

The S key toggles sound and music.

Madmarkus: The music tracks are saved as ogg vorbis files and the dosbox used can simulate cd audio tracks with audio files. the cd "image" loaded is just file telling what file is what cd track:
FILE "game.gog" BINARY
TRACK 01 MODE1/2352
INDEX 01 00:00:00
FILE "Music\Track02.ogg" MP3
TRACK 02 AUDIO
INDEX 01 00:00:00
FILE "Music\Track03.ogg" MP3
TRACK 03 AUDIO
INDEX 01 00:00:00
FILE "Music\Track04.ogg" MP3
TRACK 04 AUDIO
INDEX 01 00:00:00
FILE "Music\Track05.ogg" MP3
TRACK 05 AUDIO
INDEX 01 00:00:00
FILE "Music\Track06.ogg" MP3
TRACK 06 AUDIO
INDEX 01 00:00:00
FILE "Music\Track07.ogg" MP3
TRACK 07 AUDIO
INDEX 01 00:00:00
FILE "Music\Track08.ogg" MP3
TRACK 08 AUDIO
INDEX 01 00:00:00
FILE "Music\Track09.ogg" MP3
TRACK 09 AUDIO
INDEX 01 00:00:00

i don't want to disable music, i want to know- how to lower music volume?

Open DOSBOXCarma3Dfx.conf and add MIXER CDAUDIO 50:50 (50% volume) to the line that starts imgmount. You can change the number for percentage volume level.

Line should look something like this:

imgmount d ".\CARMA\GAME.DAT" -t cdrom -fs iso MIXER CDAUDIO 40:40

no, the mixer line should go below the imgmount line

thanks, but i'm using wing95 version

What you can do, is changing the .ogg files' volume (for example with the freeware 'audacity'), but this is not really handy and it breaks the doxbox-version. For the dosboy version it is necessary (at least in version 2.0.0.63)
to add MIXER CDAUDIO 50:50 (50% volume) to the line that starts imgmount. in the file 'dosboxCARMA_single.conf' .