I think we should color the volume meter so everyone could easily see how much volume is used. I have wifi and audio volume and few other things on my systray/taskbar and all are same colors and none gives information how is it used. Reproducible: Always
Could you provide any specifics on what change you'd like?
The colour and display of the system tray icon is entirely under the control of Plasma and implemented by the desktop theme. Not sure if there is anything that can be done by KMix in this area.