kmix missing stereo slider to adjust left-right sound

[Miki800]

I refuse to believe that kmix never had those to begin with,
Kmix version:

KMix
Version 4.1
Using KDE Development Platform 4.8.5 (4.8.5)

I only have the volume levels slider in kmix, but there is no visible configuration to restore the missing
(assuming it is actually missing due to a bug, and not by design)
left-right stereo sound adjustment slider.

(in the alsamixergui, there is a way to control left-right volume, but it looks very ancient and primitive gui-wise compared to kmix, imho)

[GreyGeek]

When KMix is showing the vertical channels right click on the icon at the top of each slider and check the box "Split Channel".