sound editing

[Silberio]

hi there

i got a problem when try i replace a sound file...well...this is my "nightmare" LOL:

 

i downloaded a 2 weapons, whit a silencer, but they use same sound, so it dosnt fit the model, lets say, a silenced 45. auto/colt 1911, but still sounds as a 45. auto, so i downloaded the sound of a silenced bullet shot, but i cant replace it, it givs me errors, or in game it sounds like a TV whitout signal, could some1 tell me how i can edit it?

 

PS: i downloaded realistic weapon sounds, and it goes' perfectly, but it never works whit mah' sounds...