Windows Volume Control - some aplications lose own volume level

HI!-I'm struggling with problem of losing application-specific volume settings inside expanded volume mixer panel.
I open the mixer and set application specific volume by decreasing the slider to value lower then 100%, the limited volume is then used for some period but at random moments the audio output from this application is loud again. If I open volume control and see the slider it's expectably being set to maximum value (100%). I need to prevent these resets (force the adjusted volume to remain). Is there an usual culprit?

Having total three audio devices attached to system:
- integrated onboard audio chip (not default device, used ad hoc for selected few applications)
- integrated LCD audio speakers (default sound device, used for most apps, is removed when LCD goes to sleep and added back when it wakes up)
- external USB audio (not default)
Volume resets may be caused when LCD sleeps/awakes and audio devices configuration frequently change

If I review the sound configuration inside soundvolumeview utility, I see the applications where is the volume changed, but assigned to different device (the external USB device). It looks messy. I need to know where are the volume levels stored and start to monitoring them for background changes.

Thanks for ideas.