Sound bug after installing another program

Hello all. I'll explain some facts. Wow was working perfect but then I installed Discord and sound went off, I resolved that selecting another sound device in wow options in game. But problem is that now I installed 1 other game in my computer (to play with a local friend) and wow sound is off no matter what sound device I select in wow or in this other game. I tried updating drivers, they were up to date.

I read in google that someone solved this changing directx11 to directx9 option for wow. My computer uses directx11 according to dxdiag.
--> Do anyone know how to change my use of directx11 to 9 for wow?

or any other help tip is appreciated.

WoW (at least wotlk if that's what you play) only uses 9, but this has little to do with your problem.

Are you sure WoW isn't muted in the volume mixer of your computer?

it is not muted :(
yes i play wotlk, in windows 7 x64

hehe its solved, i had turned off a sound system service at windows startup hehehe

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