Some have complained about some of the music in COD4. I ran across this in
cod4central.com.
Turning off the in game music (PC version) - To disable the music in the game (in case you want to listen to your own), browse to your COD4 folder, (something like "C:\Program Files\Activision\Call of Duty 4 - Modern Warfare") and rename the "Miles" folder to "MilesMUSICOFF". This way the music will be disabled in the game. If you ever want the music back, just rename the folder back to "Miles".
I do not know if this works in the Ace Mod.
I have not tried this myself because I am not sick of "Trigger Happy" yet.