Make a 0 byte sound file by making a text file and changing its extension to wav. Once you do that, duplicate it a bunch of times and rename it to these:
drum-hitclap
drum-hitfinish
drum-hitwhistle
normal-hitclap
normal-hitfinish
normal-hitwhistle
soft-hitclap
soft-hitfinish
soft-hitwhistle
then, grab one sound that you want to use, duplicate it couple times again and call it the following:
drum-hitnormal
normal-hitnormal
soft-hitnormal
finally, go to skin.ini and under [General] write this:
LayeredHitSounds: 1
I hope this helped.