I did not bother to read the above posts, though did glance briefly here and there as I scrolled down. I don't believe much of any of what I looked at did anything to actually assist Vlada.
As far as updating this post - that is why I returned here - it took several days of working with Vlada and she with the Presonus folks and a whole bunch of digging through online information and trying various things and all of that.
1) As it turns out, there is some kind of issue with the Presonus drivers for the StudioLive 24.22. audio interface that Vlada has been trying to get working - that this thread was created for discussing.
2) Sonar AS WELL, seems to have been failing when in its initialization processing - dealing with some strange situation, from the audio interface, that in my opinion Sonar should have handled a bit more gracefully than it failing. It is also important to note that in Sonar's defense - somewhat - when there is bad logic in an audio interface's drivers, in a way all bets are off, HOWEVER Sonar could have displayed some error message and handled the condition - since the audio interface wasn't even physically connected and Sonar still failed.
3) it turns out that PART of the issue was that the Presonus driver installation process itself made a bit of a mess of its own installation files - and after I did some research into it - Vlada was able to manually update the drivers to point to the proper paths and settings for the interface to finally show up as working in Windows 10.
4) BUT - even with the interface seen by Windows, and indicating itself working properly, and Sonar finally opening, there is STILL the condition that there is no sound heard on playback, AND the meters do not show any levels.
So - there doesn't seem anything that the Presonus folks will deal with further - Vlada's interface is discontinued and long out of warranty - I cannot speak for Vlada - I think this reflects where she is after her conversations with their tech support folks.
As far as SONAR goes - it would be nice if they could adjust whatever bit of initialization code needed - so that such a condition can be handled in a way that doesn't crash Sonar, and generates an error message to inform the user to the error condition.
Vlada does have a potential temporary solution - in that she has a much less feature-rich, but functioning M-Audio / Avid USB interface she can use while reviewing options on looking at alternate interfaces for purchase so she can meet her needs with something that will work on her monster Windows 10 PC.
Bob Bone