Alsa audio Balance Left-Right on USB Card

[sandrology]

moOde has always used ALSA, since 2013.

There is almost no information in your post that could be used for troubleshooting. Try posting the make/model of your audio device, version of moOde, etc.

Ok 
I have the last version of Moode. My device is Cambridge Audio CX81. this is the output when send aplay -l command:
card 2: C20 [CA CXA81 2.0], device 0: USB Audio [USB Audio]

I would like to set The balance L/R. I tried 

Code:

amixer -c 2 sset Master 10%,90%

But doesn't works

Thanks
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