I have one output audio if I open sonar the sound from you tube is gone if i close sonar the sound return !
 
I think it must use tow sound at the same time?

Check the sample rate in Windows (Advanced tab on the Properties for the default playback device in the Windows Control Panel > Sound Playback tab) and make sure it is the same as SONAR.

scook
Check the sample rate in Windows (Advanced tab on the Properties for the default playback device in the Windows Control Panel > Sound Playback tab) and make sure it is the same as SONAR.

Thanks it work now

Wow, I was having the same issue.  Couldn't figure out what changed, since I used to be able to play along with streaming audio on the Internet, including YouTube.  I should have guessed it was the sample rate.
I use Focusrite Saffire Pro 24 with Saffire MixControl software....which seems to have a mind of it's own and changes sample rates and ASIO buffer size randomly.