Thanks for reply ProjectM!
I agree, ASIO drivers give almost to none ltency with my current soundcard. And yes, i don't think any of "Windows" programs are using ASIO drivers. I did try to use 44100Khz on both, the soundcard and Sonar but it didn't help. And i don't have onboard audio enabled from BIOS. Only audio connections Windows sees are those coming from my ESP1010e, digital and analog. And neither one of those could get any signal from Windows programs.
And it doesn't help if i close Sonar, sounds aren't coming back. Before, when i've used Sonar with this soundcard, it has indeed stopped playing from Sonar for as long as some other program has been focused. But suddenly it isn't working anymore.
Maybe something has changed with Windows, in the way it handles drivers. Best solution so far is what you suggested, that Windows tries to route the audio signal to some path that isn't actually in use.
I do like pickles, but not when they are the main meal! :D