First some definitions :
- Device : Is the hardware your computer uses to output sound. In your case you have 2 devices : the intel HDA and the Audigy. (If you have a separate graphic card with HDMI output, you might have a third.
- Alsa : is the layer through which applications talk to the hardware (devices). but its a bit more then that : with proper (read complex) configuration you can do wonders with it (upmixing, bridging ouptputs...). Big downside : any device can be used by only one application at a time.
- Pulseaudio : is a sound server. its a layer (completely optional) that sits between applications and ALSA. It can do everything ALSA can and a bit more. And since it sits between ALSA and the applications it can mix streams : many apps can play at the same time.
I suspect that the non-kde applications are trying to use the sound devices for themselves, thus not allowing anyone else access. Maybe even trying to use the wrong device : if you set the sound preferences using KDE, it will unfortunately only apply to KDE applications).
If you want easy configuration I suggest you install pulseaudio and work up from there.
if you want to configure ALSA, start with a ~/.asoundrc
. Once you chew through the beginnings, it's quite simple. I had to do it, and documented my progress here
Personnally I don't like PulseAudio, and I'd go with asoundrc;
Unfortunately this Information is all I can give you, since your description doesn't give me enough hints as to figure out what is really going on. I hope you can use all this to figure out what is going on, and maybe even fix it
Don't hesitate to post back.
Also the software has absolutely no idea whether something is connected to an audio output or not.
Theory : If a device is taken by another application, kde can't access it and decides it can't be used => asks if you want to forget about it.