This is actually bad advice.
GMs generally aren’t going to tell you which particular software resulted in a ban. That would give exploit/bot writers ammunition as to what works and what doesn’t.
In saying that for sound replacements Blizzard are generally okay with people replacing sounds by overriding wow’s data format’s loading system as long as you are not distributing copyrighted sounds
AKA
Modifying game files = not okay
Put a sound file in a special folder in the wow folder thereby overriding that same sound from loading = Okay
Recording a small sample from a CD you own and using that in game = Okay
Recording that same sample and uploading it to Curse.com as part of your own sound kit = Not Okay.
Downloading a public domain sound , modifying it then uploading it to curse.com as part of your own sound kit = Okay (provided you include the appropriate license files)