Creating your on custom ambient background sounds. Thanks to adwamslayer for this tutorial.
For this you will need a music editing program, one that I use is called 'FreeRip' because its free.
Look hear: www.mgshareware.com
First of all, you need to check the properties of the custom sound file. Right click on it go to properties.
In this new box, click on the summary tab, and select advanced, scroll down and it will show you the bit-rate, file extension and sample rate ect. Note this information.
You will now need to note one of the stock ambient sound files properties, so look in the PAK files until you find one. (pak2.pk3/sound/ambient)
You will need to look at the sample rate, file extension ect of this file as well, note it.
Compare the two and see what needs changing, if nothing then that's great! but if so then this is when FreeRip needs to be used.
Load up freerip. On the top menu bar click on tools, then select 'convert single audio file'. Import your file and select a new bit-rate of 128kbits for the new file and/or change the channels and/or the file extension, and choose an output path and convert.
The reason for this is so CoD will be able to read the file properly.
Next rename the file to amb_????_ext.mp3 where the ???? you can have what ever you want. I will call mine amb_cricket_ext.mp3
Now make a new folder in main called sound. Open up sound and make another folder called ambient. It should look like main/sound/ambient Now place your file in the ambient folder.
Now the hardest part, the csv file. Open up notepad and enter this information (in the blue text +highlight):
# Tutorial sounds,,,,,,,,,,,,,,,
The text highlighted in red is called the sound alias, and this is what we place in the gsc file to play the music.
Now save the file as "yourmapname.csv" Now where does it go? Make a new folder in main called soundaliases and place the csv file in there. It should look like main/soundaliases/yourmapname.csv
Now the gsc file. Load up notepad and copy and paste this information (in blue text + highlight):
setCullFog (0, 5000, .32, .33, .40, 0);
game["allies"] = "british";
game["axis"] = "german";
game["attackers"] = "allies";
game["defenders"] = "axis";
game["american_soldiertype"] = "airborne";
game["american_soldiervariation"] = "normal";
game["german_soldiertype"] = "wehrmacht";
game["german_soldiervariation"] = "normal";
Notice how the highlights are the same? Save this as "yourmapname.bsp" and place it in the main/maps/mp folder. Nothing is needed to be done to your map in radiant, just make sure that all the files that are used in to create the custom ambient sounds are named the same as your map (apart from the sound file)
By Adam, aka adwamslayer
Credit goes to: Pharao_FS, for the tutorial on how to add sounds in multiplayer.