Here is a little somthing i tweeked. All footsteps are now louder than before. Also within most custom maps all ambient sounds, background noises, are gone.
Place these files within CProgram Files\Steam\SteamApps\**Your Name**\day of defeat source\dod\scripts
You can tweek them yourselves as well, just open a file and add bigger or lower numbers just to the Volume section wherever it says it. I'm not resonsible for any messups.
If you need help PM me.