I'm setting up TDE-based Debian on a new machine and I've run into a problem I have not 
experienced on any other of my machines with similar configurations: KMix can't control audio 
volume. More specifically, I have two audio outputs: an HDMI one (via nVidia card with 
proprietary drivers) and a front panel audio jack. Sound works correctly on both outputs and I 
can control it with pavucontrol (PulseAudio sound mixer). However:

1. KMix master slider that appears after clicking on the tray icon does absolutely nothing.
2. When I open the mixer window in KMix it recognizes PulseAudio as an audio device. There is just 
one volume slider and it does nothing.
3. Another recognized audio device is HD-Audio Generic. This has a bunch of output sliders and the 
sliders work correctly (i.e. they change the volume) when the sound is directed to headphones, 
but not when it's directed to HDMI (output change done via pavucontrol).
4. The final audio device recognized by KMix is HDA Nvidia. This only has seven toggles labales 
IEC958. First toggle mutes/unmutes the sound, the remaining ones don't seem to be doing anything.

I'm puzzled. This is the first time I see KMix master slider not working at all, even though I 
have pulseaudio set up on all my other machines with TDE. Any thoughts or suggestions?

Janek