copy the sound folder and all of its contents to the localdata directory of your STO Install.

For instance, I have a Steam install and my location is "E:\Games\Steam\SteamApps\common\Star Trek Online\Star Trek Online\Live\Localdata"

There is a localdata sitting in the root directory for my Steam install, this is not the location.  The final directory path should look something like this:

"E:\Games\Steam\SteamApps\common\Star Trek Online\Star Trek Online\Live\Localdata\sound\win32"
<-- All of the FSB files should be in this directory.