Issue about replacing sound，or can't hear a big part of all the sounds in ostim scenes

[AsianGodStick]

Could you please tell me how to make a simple mod to replace the sound？just followed the experience when doing this for sexlab，I made a mod like this 'my mod folder'\Sound\fx\0SA\class'extra'，but failed.
By the way，I think I have an issue similar to that “sound not working” one，as I can only hear sound at cum shooting and spanking time，I tried blowjob，boobjob（excuse me if this word or my grammar is incorrect cause I'm not a native English speaker），handjob，and so on，such scenes all are in silent.
Or maybe in fact my method of replacing sounds is right，but zero of sound files I changed is included in these few sounds I can hear.