"+miles_channels 2" doesn't work, stereo and suround issues - Season 15

I tried to launch my game after the update and an error message appeared.

After that, I checked the integrity of the game files on Steam to maybe fix the problem but it didn’t change anything.

When I read the error message, I understood that this came from the "+miles_channels 2" launch option command that I added to force the sound of the game into stereo.

Playing mainly in stereo, it bothers me a lot that this command no longer works:/

Is there a solution? Do other players have this mistake?