The only way I know of is manually editing the configuration text files. Go to /home/yourusername/.tome/3.0/settings/ (if on Linux - I'm not sure exactly where the settings are stored on other operating systems) where you should see a file called audio.cfg.
Change the first line of audio.cfg to read:
enable = 0
If you don't have that file then create it there and add the line above.
While you're at it, you might also want to disable Babyface in engine.cfg. (Babyface is the new module-handling UI that I personally happen to regard as horrible.)