Weird. Was working on a tune and after stopping the track for a second, I hit play and it wouldn't. I looked around and saw that my sample rate and bit depth moved spontaneously to  16/44.1 from my normal 24/96. when I hit play i get a message saying my project sample rate is different from my audio card.
 
How do i get it back, when I try and click on the sample rate/bit depth indicator under the time clock nothing happens. Must be something stupid but I can't figure it out.

Hi. Is this happening on more than one project? Does Windows and SONAR have the same sample rate an bit depth? Do you have shared drivers with other programs enabled in Preferences (P), Audio, Playback and Recording? Can you change it back in Preferences, Audio, Driver Settings? Do you have any other programs running?
Best of luck.