I have installed Xfce4 on Debian testing. I'm using ALSA for sound driver. If I decrease volume level by using sound control applet in Xfce panel, there is no problem till "zero level". If I decrease volume to zero, I can not increase. (I can increase, but there is no sound).
After digging a bit, I found out that if I decrease master channel volume to zero level, suddenly speaker channel mutes (and vice-versa).
How can I fix the issue?
I changed theme and stuff (I don't know what I did exactly) but now it works as expected.
There is no problem right now.