crpg sounds modding

[no_rules_just_play]

hey guys i know its not your category, but i think you guys are the most experienced with modding so maybe someone can help me?
i didnt know a better section than this, so move me if you know where i should go.

but, this is my question: there is a sounds-folder in the crpg-module-folder, i wanted to change the whistle-sound with a file i made. i saw there were two whistle files, the one was vc_whistle.mp3 and the other one whistle.mp3
this is what i tried:
i made a whistle.mp3 file and a vc_whistle file (both with the same duck sounds for fuma, but i just gave them another name as the original files also where the same)
i replaced the original files with my 'duck-files'
=> didnt work
i did the same but this time a rendered my duck files to .ogg-files
=> this also didnt work

i could replace woman_yell_2 (mount and blade sounds folder) with the quackquack sounds for fuma tough

TL;DR: can i replace sound-files in the crpg-module-folder with my own files or can i only do this in the moundandbladewarband-soundfolder?

thanks for reading,

no_rules

[Thranduil]

Uhm. you should be able to...as long as the filename is exactly the same and so is the file type (.ogg usually).  Also, the whistle and vc_whistle are not .mp3, they are WAVE files (.WAV).

[no_rules_just_play]

wav files, that could be the problem. stupid me, didnt check the files 
thanks man, i wouldnt have tought about taking a closer look at the file if you hadnt seen this