I have a sound problem could you help me please?

I’m creating a game with SDL and SDL_Mixer, but i can’t realise a volume
control. However i use Mix_Volume(int channel,int volume) or
Mix_VolumeMusic(int volume) with for all volume between 0 to 128 but this
made no effect on the music.wav . I have looked a lot of tutorial on the web
and they do like me with a int volume (0-128) so i don’t understand why this
doesn’t work.
I’m a student, and it’s for a projet also if you could answer me quickly
please and thank you for all._________________________________________________________________
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